# leetcode

**Repository Path**: yty0801/leetcode

## Basic Information

- **Project Name**: leetcode
- **Description**: LeetCode Problems' Solutions 
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2021-03-23
- **Last Updated**: 2022-06-09

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README


LeetCode
========

### LeetCode Algorithm

(Notes: "🔒" means you need to buy a book from Leetcode)


| # | Title | Solution | Difficulty |
|---| ----- | -------- | ---------- |
|1803|[Count Pairs With XOR in a Range](https://leetcode.com/problems/count-pairs-with-xor-in-a-range/) | [C++](./algorithms/cpp/countPairsWithXorInARange/CountPairsWithXorInARange.cpp)|Hard|
|1802|[Maximum Value at a Given Index in a Bounded Array](https://leetcode.com/problems/maximum-value-at-a-given-index-in-a-bounded-array/) | [C++](./algorithms/cpp/maximumValueAtAGivenIndexInABoundedArray/MaximumValueAtAGivenIndexInABoundedArray.cpp)|Medium|
|1801|[Number of Orders in the Backlog](https://leetcode.com/problems/number-of-orders-in-the-backlog/) | [C++](./algorithms/cpp/numberOfOrdersInTheBacklog/NumberOfOrdersInTheBacklog.cpp)|Medium|
|1800|[Maximum Ascending Subarray Sum](https://leetcode.com/problems/maximum-ascending-subarray-sum/) | [C++](./algorithms/cpp/maximumAscendingSubarraySum/MaximumAscendingSubarraySum.cpp)|Easy|
|1799|[Maximize Score After N Operations](https://leetcode.com/problems/maximize-score-after-n-operations/submissions/) | [C++](./algorithms/cpp/maximizeScoreAfterNOperations/MaximizeScoreAfterNOperations.cpp)|Hard|
|1798|[Maximum Number of Consecutive Values You Can Make](https://leetcode.com/problems/maximum-number-of-consecutive-values-you-can-make/submissions/) | [C++](./algorithms/cpp/maximumNumberOfConsecutiveValuesYouCanMake/MaximumNumberOfConsecutiveValuesYouCanMake.cpp)|Medium|
|1797|[Design Authentication Manager](https://leetcode.com/problems/design-authentication-manager/) | [C++](./algorithms/cpp/designAuthenticationManager/DesignAuthenticationManager.cpp)|Medium|
|1796|[Second Largest Digit in a String](https://leetcode.com/problems/second-largest-digit-in-a-string/) | [C++](./algorithms/cpp/secondLargestDigitInAString/SecondLargestDigitInAString.cpp)|Easy|
|1793|[Maximum Score of a Good Subarray](https://leetcode.com/problems/maximum-score-of-a-good-subarray/) | [C++](./algorithms/cpp/maximumScoreOfAGoodSubarray/MaximumScoreOfAGoodSubarray.cpp)|Hard|
|1792|[Maximum Average Pass Ratio](https://leetcode.com/problems/maximum-average-pass-ratio/) | [C++](./algorithms/cpp/maximumAveragePassRatio/MaximumAveragePassRatio.cpp)|Medium|
|1791|[Find Center of Star Graph](https://leetcode.com/problems/find-center-of-star-graph/) | [C++](./algorithms/cpp/findCenterOfStarGraph/FindCenterOfStarGraph.cpp)|Medium|
|1790|[Check if One String Swap Can Make Strings Equal](https://leetcode.com/problems/check-if-one-string-swap-can-make-strings-equal/) | [C++](./algorithms/cpp/checkIfOneStringSwapCanMakeStringsEqual/CheckIfOneStringSwapCanMakeStringsEqual.cpp)|Easy|
|1787|[Make the XOR of All Segments Equal to Zero](https://leetcode.com/problems/make-the-xor-of-all-segments-equal-to-zero/) | [C++](./algorithms/cpp/makeTheXorOfAllSegmentsEqualToZero/MakeTheXorOfAllSegmentsEqualToZero.cpp)|Hard|
|1786|[Number of Restricted Paths From First to Last Node](https://leetcode.com/problems/number-of-restricted-paths-from-first-to-last-node/) | [C++](./algorithms/cpp/numberOfRestrictedPathsFromFirstToLastNode/NumberOfRestrictedPathsFromFirstToLastNode.cpp)|Medium|
|1785|[Minimum Elements to Add to Form a Given Sum](https://leetcode.com/problems/minimum-elements-to-add-to-form-a-given-sum/) | [C++](./algorithms/cpp/minimumElementsToAddToFormAGivenSum/MinimumElementsToAddToFormAGivenSum.cpp)|Medium|
|1784|[Check if Binary String Has at Most One Segment of Ones](https://leetcode.com/problems/check-if-binary-string-has-at-most-one-segment-of-ones/) | [C++](./algorithms/cpp/checkIfBinaryStringHasAtMostOneSegmentOfOnes/CheckIfBinaryStringHasAtMostOneSegmentOfOnes.cpp)|Easy|
|1782|[Count Pairs Of Nodes](https://leetcode.com/problems/count-pairs-of-nodes/) | [C++](./algorithms/cpp/countPairsOfNodes/CountPairsOfNodes.cpp)|Hard|
|1781|[Sum of Beauty of All Substrings](https://leetcode.com/problems/sum-of-beauty-of-all-substrings/) | [C++](./algorithms/cpp/sumOfBeautyOfAllSubstrings/SumOfBeautyOfAllSubstrings.cpp)|Medium|
|1780|[Check if Number is a Sum of Powers of Three](https://leetcode.com/problems/check-if-number-is-a-sum-of-powers-of-three/) | [C++](./algorithms/cpp/checkIfNumberIsASumOfPowersOfThree/CheckIfNumberIsASumOfPowersOfThree.cpp)|Medium|
|1779|[Find Nearest Point That Has the Same X or Y Coordinate](https://leetcode.com/problems/find-nearest-point-that-has-the-same-x-or-y-coordinate/) | [C++](./algorithms/cpp/findNearestPointThatHasTheSameXOrYCoordinate/FindNearestPointThatHasTheSameXOrYCoordinate.cpp)|Easy|
|1774|[Closest Dessert Cost](https://leetcode.com/problems/closest-dessert-cost/) | [C++](./algorithms/cpp/closestDessertCost/ClosestDessertCost.cpp)|Medium|
|1773|[Count Items Matching a Rule](https://leetcode.com/problems/count-items-matching-a-rule/) | [C++](./algorithms/cpp/countItemsMatchingARule/CountItemsMatchingARule.cpp)|Easy|
|1769|[Minimum Number of Operations to Move All Balls to Each Box](https://leetcode.com/problems/minimum-number-of-operations-to-move-all-balls-to-each-box/) | [C++](./algorithms/cpp/minimumNumberOfOperationsToMoveAllBallsToEachBox/MinimumNumberOfOperationsToMoveAllBallsToEachBox.cpp)|Medium|
|1768|[Merge Strings Alternately](https://leetcode.com/problems/merge-strings-alternately/) | [C++](./algorithms/cpp/mergeStringsAlternately/MergeStringsAlternately.cpp)|Easy|
|1763|[Longest Nice Substring](https://leetcode.com/problems/longest-nice-substring/) | [C++](./algorithms/cpp/longestNiceSubstring/LongestNiceSubstring.cpp)|Easy|
|1761|[Minimum Degree of a Connected Trio in a Graph](https://leetcode.com/problems/minimum-degree-of-a-connected-trio-in-a-graph/) | [C++](./algorithms/cpp/minimumDegreeOfAConnectedTrioInAGraph/MinimumDegreeOfAConnectedTrioInAGraph.cpp)|Hard|
|1760|[Minimum Limit of Balls in a Bag](https://leetcode.com/problems/minimum-limit-of-balls-in-a-bag/) | [C++](./algorithms/cpp/minimumLimitOfBallsInABag/MinimumLimitOfBallsInABag.cpp)|Medium|
|1759|[Count Number of Homogenous Substrings](https://leetcode.com/problems/count-number-of-homogenous-substrings/) | [C++](./algorithms/cpp/countNumberOfHomogenousSubstrings/CountNumberOfHomogenousSubstrings.cpp)|Medium|
|1758|[Minimum Changes To Make Alternating Binary String](https://leetcode.com/problems/minimum-changes-to-make-alternating-binary-string/) | [C++](./algorithms/cpp/minimumChangesToMakeAlternatingBinaryString/MinimumChangesToMakeAlternatingBinaryString.cpp)|Easy|
|1755|[Closest Subsequence Sum](https://leetcode.com/problems/closest-subsequence-sum/) | [C++](./algorithms/cpp/closestSubsequenceSum/ClosestSubsequenceSum.cpp)|Hard|
|1754|[Largest Merge Of Two Strings](https://leetcode.com/problems/largest-merge-of-two-strings/) | [C++](./algorithms/cpp/largestMergeOfTwoStrings/LargestMergeOfTwoStrings.cpp)|Medium|
|1753|[Maximum Score From Removing Stones](https://leetcode.com/problems/maximum-score-from-removing-stones/) | [C++](./algorithms/cpp/maximumScoreFromRemovingStones/MaximumScoreFromRemovingStones.cpp)|Medium|
|1752|[Check if Array Is Sorted and Rotated](https://leetcode.com/problems/check-if-array-is-sorted-and-rotated/) | [C++](./algorithms/cpp/checkIfArrayIsSortedAndRotated/CheckIfArrayIsSortedAndRotated.cpp)|Easy|
|1751|[Maximum Number of Events That Can Be Attended II](https://leetcode.com/problems/maximum-number-of-events-that-can-be-attended-ii/) | [C++](./algorithms/cpp/maximumNumberOfEventsThatCanBeAttended/MaximumNumberOfEventsThatCanBeAttended.II.cpp)|Hard|
|1750|[Minimum Length of String After Deleting Similar Ends](https://leetcode.com/problems/minimum-length-of-string-after-deleting-similar-ends/) | [C++](./algorithms/cpp/minimumLengthOfStringAfterDeletingSimilarEnds/MinimumLengthOfStringAfterDeletingSimilarEnds.cpp)|Medium|
|1749|[Maximum Absolute Sum of Any Subarray](https://leetcode.com/problems/maximum-absolute-sum-of-any-subarray/) | [C++](./algorithms/cpp/maximumAbsoluteSumOfAnySubarray/MaximumAbsoluteSumOfAnySubarray.cpp)|Medium|
|1748|[Sum of Unique Elements](https://leetcode.com/problems/sum-of-unique-elements/) | [C++](./algorithms/cpp/sumOfUniqueElements/SumOfUniqueElements.cpp)|Easy|
|1734|[Decode XORed Permutation](https://leetcode.com/problems/decode-xored-permutation/) | [C++](./algorithms/cpp/decodeXORedPermutation/DecodeXoredPermutation.cpp)|Medium|
|1733|[Minimum Number of People to Teach](https://leetcode.com/problems/minimum-number-of-people-to-teach/) | [C++](./algorithms/cpp/minimumNumberOfPeopleToTeach/MinimumNumberOfPeopleToTeach.cpp)|Medium|
|1732|[Find the Highest Altitude](https://leetcode.com/problems/find-the-highest-altitude/) | [C++](./algorithms/cpp/findTheHighestAltitude/FindTheHighestAltitude.cpp)|Easy|
|1605|[Find Valid Matrix Given Row and Column Sums](https://leetcode.com/problems/find-valid-matrix-given-row-and-column-sums/) | [C++](./algorithms/cpp/FindValidMatrixGivenRowAndColumnSums/FindValidMatrixGivenRowAndColumnSums.cpp)|Medium|
|1573|[Number of Ways to Split a String](https://leetcode.com/problems/number-of-ways-to-split-a-string/) | [C++](./algorithms/cpp/NumberOfWaysToSplitString/NumberOfWaysToSplitString.cpp)|Medium|
|1556|[Thousand Separator](https://leetcode.com/problems/thousand-separator/) | [C++](./algorithms/cpp/thousandSeparator/ThousandSeparator.cpp)|Easy|
|1551|[Minimum Operations to Make Array Equal](https://leetcode.com/problems/minimum-operations-to-make-array-equal/) | [C++](./algorithms/cpp/minimumOperationsToMakeArrayEqual/MinimumOperationsToMakeArrayEqual.cpp)|Medium|
|1550|[Three Consecutive Odds](https://leetcode.com/problems/three-consecutive-odds/) | [C++](./algorithms/cpp/threeConsecutiveOdds/ThreeConsecutiveOdds.cpp)|Easy|
|1541|[Minimum Insertions to Balance a Parentheses String](https://leetcode.com/problems/minimum-insertions-to-balance-a-parentheses-string/) | [C++](./algorithms/cpp/minimumInsertionsToBalanceAParenthesesString/MinimumInsertionsToBalanceAParenthesesString.cpp)|Medium|
|1535|[Find the Winner of an Array Game](https://leetcode.com/problems/find-the-winner-of-an-array-game/) | [C++](./algorithms/cpp/findTheWinnerOfAnArrayGame/FindTheWinnerOfAnArrayGame.cpp)|Medium|
|1525|[Number of Good Ways to Split a String](https://leetcode.com/problems/number-of-good-ways-to-split-a-string/) | [C++](./algorithms/cpp/numberOfGoodWaysToSplitAString/NumberOfGoodWaysToSplitAString.cpp)|Medium|
|1524|[Number of Sub-arrays With Odd Sum](https://leetcode.com/problems/number-of-sub-arrays-with-odd-sum/) | [C++](./algorithms/cpp/numberOfSubArraysWithOddSum/NumberOfSubArraysWithOddSum.cpp)|Medium|
|1523|[Count Odd Numbers in an Interval Range](https://leetcode.com/problems/count-odd-numbers-in-an-interval-range/) | [C++](./algorithms/cpp/countOddNumbersInAnIntervalRange/CountOddNumbersInAnIntervalRange.cpp)|Easy|
|1513|[Number of Substrings With Only 1s](https://leetcode.com/problems/number-of-substrings-with-only-1s/) | [C++](./algorithms/cpp/numberOfSubstringsWithOnly1s/NumberOfSubstringsWithOnly1s.cpp)|Medium|
|1470|[Shuffle the Array](https://leetcode.com/problems/shuffle-the-array/) | [C++](./algorithms/cpp/shuffleTheArray/ShuffleTheArray.cpp)|Easy|
|1464|[Maximum Product of Two Elements in an Array](https://leetcode.com/problems/maximum-product-of-two-elements-in-an-array/) | [C++](./algorithms/cpp/maximumProductOfTwoElementsInAnArray/MaximumProductOfTwoElementsInAnArray.cpp)|Easy|
|1460|[Make Two Arrays Equal by Reversing Sub-arrays](https://leetcode.com/problems/make-two-arrays-equal-by-reversing-sub-arrays/) | [C++](./algorithms/cpp/twoArraysEqualByReversingSubArrays/MakeTwoArraysEqualByReversingSubArrays.cpp)|Easy|
|1376|[Time Needed to Inform All Employees](https://leetcode.com/problems/time-needed-to-inform-all-employees/) | [C++](./algorithms/cpp/timeNeededToInformAllEmployees/TimeNeededToInformAllEmployees.cpp)|Medium|
|1353|[Maximum Number of Events That Can Be Attended](https://leetcode.com/problems/maximum-number-of-events-that-can-be-attended/) | [C++](./algorithms/cpp/maximumNumberOfEventsThatCanBeAttended/MaximumNumberOfEventsThatCanBeAttended.cpp)|Medium|
|1333|[Filter Restaurants by Vegan-Friendly, Price and Distance](https://leetcode.com/problems/filter-restaurants-by-vegan-friendly-price-and-distance/) | [C++](./algorithms/cpp/filterRestaurantsByVeganFriendlyPriceAndDistance/FilterRestaurantsByVeganFriendlyPriceAndDistance.cpp)|Medium|
|1207|[Unique Number of Occurrences](https://leetcode.com/problems/unique-number-of-occurrences/) | [C++](./algorithms/cpp/uniqueNumberOfOccurrences/Unique-Number-of-Occurrences.cpp)|Easy|
|1170|[Compare Strings by Frequency of the Smallest Character](https://leetcode.com/problems/compare-strings-by-frequency-of-the-smallest-character/) | [C++](./algorithms/cpp/compareStringsByFrequencyOfTheSmallestCharacter/CompareStringsByFrequencyOfTheSmallestCharacter.cpp)|Easy|
|1071|[Greatest Common Divisor of Strings](https://leetcode.com/problems/greatest-common-divisor-of-strings/) | [C++](./algorithms/cpp/greatestCommonDivisorOfStrings/GreatestCommonDivisorOfStrings.cpp)|Easy|
|1030|[Matrix Cells in Distance Order](https://leetcode.com/problems/matrix-cells-in-distance-order/) | [C++](./algorithms/cpp/matrixCellsInDistanceOrder/MatrixCellsInDistanceOrder.cpp)|Easy|
|1029|[Two City Scheduling](https://leetcode.com/problems/two-city-scheduling/) | [C++](./algorithms/cpp/twoCityScheduling/TwoCityScheduling.cpp)|Easy|
|1028|[Recover a Tree From Preorder Traversal](https://leetcode.com/problems/recover-a-tree-from-preorder-traversal/) | [C++](./algorithms/cpp/recoverATreeFromPreorderTraversal/recoverATreeFromPreorderTraversal.cpp)|Hard|
|1024|[Video Stitching](https://leetcode.com/problems/video-stitching/) | [C++](./algorithms/cpp/videoStitching/VideoStitching.cpp)|Medium|
|993|[Cousins in Binary Tree](https://leetcode.com/problems/cousins-in-binary-tree/) | [C++](./algorithms/cpp/cousinsInBinaryTree/CousinsInBinaryTree.cpp)|Easy|
|991|[Broken Calculator](https://leetcode.com/problems/broken-calculator/) | [C++](./algorithms/cpp/brokenCalculator/BrokenCalculator.cpp)|Medium|
|990|[Satisfiability of Equality Equations](https://leetcode.com/problems/satisfiability-of-equality-equations/) | [C++](./algorithms/cpp/satisfiabilityOfEqualityEquations/SatisfiabilityOfEqualityEquations.cpp)|Medium|
|989|[Add to Array-Form of Integer](https://leetcode.com/problems/add-to-array-form-of-integer/) | [C++](./algorithms/cpp/addToArrayFormOfInteger/AddToArrayFormOfInteger.cpp)|Easy|
|988|[Smallest String Starting From Leaf](https://leetcode.com/problems/smallest-string-starting-from-leaf/) | [C++](./algorithms/cpp/smallestStringStartingFromLeaf/SmallestStringStartingFromLeaf.cpp)|Medium|
|987|[Vertical Order Traversal of a Binary Tree](https://leetcode.com/problems/vertical-order-traversal-of-a-binary-tree/) | [C++](./algorithms/cpp/verticalOrderTraversalOfABinaryTree/VerticalOrderTraversalOfABinaryTree.cpp)|Medium|
|986|[Interval List Intersections](https://leetcode.com/problems/interval-list-intersections/) | [C++](./algorithms/cpp/intervalListIntersectons/IntervalListIntersections.cpp)|Medium|
|985|[Sum of Even Numbers After Queries](https://leetcode.com/problems/sum-of-even-numbers-after-queries/) | [C++](./algorithms/cpp/sumOfEvenNumbersAfterQueries/SumOfEvenNumbersAfterQueries.cpp)|Easy|
|984|[String Without AAA or BBB](https://leetcode.com/problems/string-without-aaa-or-bbb/) | [C++](./algorithms/cpp/stringWithoutAAAOrBBB/StringWithoutAAAOrBBB.cpp)|Easy|
|983|[Minimum Cost For Tickets](https://leetcode.com/problems/minimum-cost-for-tickets/) | [C++](./algorithms/cpp/minimumCostForTickets/MinimumCostForTickets.cpp)|Medium|
|982|[Triples with Bitwise AND Equal To Zero](https://leetcode.com/problems/triples-with-bitwise-and-equal-to-zero/) | [C++](./algorithms/cpp/triplesWithBitwiseANDEqualToZero/TriplesWithBitwiseAndEqualToZero.cpp)|Hard|
|981|[Time Based Key-Value Store](https://leetcode.com/problems/time-based-key-value-store/) | [C++](./algorithms/cpp/timeBasedKeyValueStore/TimeBasedKeyValueStore.cpp)|Medium|
|980|[Unique Paths III](https://leetcode.com/problems/unique-paths-iii/) | [C++](./algorithms/cpp/uniquePaths/UniquePaths.III.cpp),[Python](./algorithms/python/uniquePaths/uniquePathsIII.py)|Hard|
|979|[Distribute Coins in Binary Tree](https://leetcode.com/problems/distribute-coins-in-binary-tree/) | [C++](./algorithms/cpp/distributeCoinsInBinaryTree/DistributeCoinsInBinaryTree.cpp)|Medium|
|978|[Longest Turbulent Subarray](https://leetcode.com/problems/longest-turbulent-subarray/) | [C++](./algorithms/cpp/longestTurbulentSubarray/LongestTurbulentSubarray.cpp),[Python](./algorithms/python/LongestTurbulentSubarray/maxTurbulenceSize.py)|Medium|
|977|[Squares of a Sorted Array](https://leetcode.com/problems/squares-of-a-sorted-array/) | [C++](./algorithms/cpp/squaresOfASortedArray/SquaresOfASortedArray.cpp), [Python](./algorithms/python/SquaresOfSortedArray/sortedSquares.py)|Easy|
|976|[Largest Perimeter Triangle](https://leetcode.com/problems/largest-perimeter-triangle/) | [C++](./algorithms/cpp/largestPerimeterTriangle/largestPerimeterTriangle.cpp), [Python](./algorithms/python/LargestPerimeterTriangle/largestPerimeter.py)|Easy|
|971|[Flip Binary Tree To Match Preorder Traversal](https://leetcode.com/problems/flip-binary-tree-to-match-preorder-traversal/) | [Python](./algorithms/python/FlipBinaryTreeToMatchPreorderTraversal/flipMatchVoyage.py)|Medium|
|969|[Pancake Sorting](https://leetcode.com/problems/pancake-sorting/) | [Python](./algorithms/python/PancakeSorting/pancakeSort.py)|Medium|
|961|[N-Repeated element in size 2N Array](https://leetcode.com/problems/n-repeated-element-in-size-2n-array/) | [C++](./algorithms/cpp/nRepeatedElementInSize2NArray/N-Repeated-Element-in-Size-2N-Array.cpp)|Easy|
|958|[Check Completeness of a Binary Tree](https://leetcode.com/problems/check-completeness-of-a-binary-tree/) | [Python](./algorithms/python/CheckCompletenessOfABinaryTree/isCompleteTree.py)|Medium|
|951|[Flip Equivalent Binary Trees](https://leetcode.com/problems/flip-equivalent-binary-trees/) | [Python](./algorithms/python/FlipEquivalentBinaryTrees/flipEquiv.py)|Medium|
|950|[Reveal Cards In Increasing Order](https://leetcode.com/problems/reveal-cards-in-increasing-order/) | [Python](./algorithms/python/RevealCardsInIncreasingOrder/deckRevealedIncreasing.py)|Medium|
|941|[Valid Mountain Array](https://leetcode.com/problems/valid-mountain-array/) | [Python](./algorithms/python/ValidMountainArray/validMountainArray.py)|Easy|
|933|[Number of Recent Calls](https://leetcode.com/problems/number-of-recent-calls/) | [C++](./algorithms/cpp/numberOfRecentCalls/NumberOfRecentCalls.cpp)|Easy|
|931|[Minimum Falling Path Sum](https://leetcode.com/problems/minimum-falling-path-sum/) | [C++](./algorithms/cpp/minimumFallingPathSum/MinimumFallingPathSum.cpp)|Medium|
|929|[Unique Email Addresses](https://leetcode.com/problems/unique-email-addresses/) | [C++](./algorithms/cpp/uniqueEmailAddresses/UniqueEmailAddresses.cpp)|Easy|
|922|[Sort Array By Parity II](https://leetcode.com/problems/sort-array-by-parity-ii/) | [C++](./algorithms/cpp/sortArrayByParity/SortArrayByParity.II.cpp)|Easy|
|914|[X of a Kind in a Deck of Cards](https://leetcode.com/problems/x-of-a-kind-in-a-deck-of-cards/) | [Python](./algorithms/python/XOfAKindInADeckOfCards/hasGroupsSizeX.py)|Easy|
|905|[Sort Array By Parity](https://leetcode.com/problems/sort-array-by-parity/) | [C++](./algorithms/cpp/sortArrayByParity/SortArrayByParity.cpp)|Easy|
|876|[Middle of the Linked List](https://leetcode.com/problems/middle-of-the-linked-list/) | [Python](./algorithms/python/MiddleOfTheLinkedList/middleOfTheLinkedList.py)|Easy|
|859|[Buddy Strings](https://leetcode.com/problems/buddy-strings/description/) | [C++](./algorithms/cpp/buddyStrings/BuddyStrings.cpp)|Easy|
|858|[Mirror Reflection](https://leetcode.com/problems/mirror-reflection/description/) | [C++](./algorithms/cpp/mirrorReflection/MirrorReflection.cpp)|Medium|
|852|[Peak Index in a Mountain Array](https://leetcode.com/problems/peak-index-in-a-mountain-array/description/) | [C++](./algorithms/cpp/peakIndexInAMountainArray/PeakIndexInAMountainArray.cpp)|Easy|
|849|[Maximize Distance to Closest Person](https://leetcode.com/problems/maximize-distance-to-closest-person/) | [Python](./algorithms/python/MaximizeDistanceToClosestPerson/maxDistToClosest.py)|Easy|
|844|[Backspace String Compare](https://leetcode.com/problems/backspace-string-compare/description/) | [C++](./algorithms/cpp/backspaceStringCompare/BackspaceStringCompare.cpp)|Easy|
|837|[Most Common Word](https://leetcode.com/problems/most-common-word/) | [C++](./algorithms/cpp/mostCommonWord/MostCommonWord.cpp)|Easy|
|830|[Positions of Large Groups](https://leetcode.com/problems/positions-of-large-groups/) | [Python](./algorithms/python/PositionsOfLargeGroups/largeGroupPositions.py)|Easy|
|820|[Short Encoding of Words](https://leetcode.com/problems/short-encoding-of-words/) | [C++](./algorithms/cpp/shortEncodingOfWords/ShortEncodingOfWords.cpp)|Medium|
|804|[Unique Morse Code Words](https://leetcode.com/problems/unique-morse-code-words/description/) | [C++](./algorithms/cpp/uniqueMorseCodeWords/UniqueMorseCodeWords.cpp)|Easy|
|771|[Jewels and Stones](https://leetcode.com/problems/jewels-and-stones/description) | [C++](./algorithms/cpp/jewelsAndStones/JewelsAndStones.cpp)|Easy|
|747|[Largest Number At Least Twice of Others](https://leetcode.com/problems/largest-number-at-least-twice-of-others/) | [Python](./algorithms/python/LargestNumberAtLeastTwiceOfOthers/dominantIndex.py)|Easy|
|746|[Min Cost Climbing Stairs](https://leetcode.com/problems/min-cost-climbing-stairs/) | [C++](./algorithms/cpp/minCostClimbingStairs/MinCostClimbingStairs.cpp), [Python](./algorithms/python/MinCostClimbingStairs/minCostClimbingStairs.py)|Easy|
|721|[Accounts Merge](https://leetcode.com/problems/accounts-merge/) | [C++](./algorithms/cpp/accountsMerge/AccountsMerge.cpp)|Medium|
|717|[1-bit and 2-bit Characters](https://leetcode.com/problems/1-bit-and-2-bit-characters/) | [Python](./algorithms/python/1-bitAnd2-bitCharacters/isOneBitCharacter.py)|Easy|
|714|[Best Time to Buy and Sell Stock with Transaction Fee](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-with-transaction-fee) | [C++](./algorithms/cpp/bestTimeToBuyAndSellStock/BestTimeToBuyAndSellStockWithTransactionFee.cpp)|Medium|
|712|[Minimum ASCII Delete Sum for Two Strings](https://leetcode.com/problems/minimum-ascii-delete-sum-for-two-strings/) | [C++](./algorithms/cpp/minimumASCIIDeleteSumForTwoStrings/MinimumAsciiDeleteSumForTwoStrings.cpp)|Medium|
|695|[Max Area of Island](https://leetcode.com/problems/max-area-of-island/) | [C++](./algorithms/cpp/maxAreaOfIsland/MaxAreaOfIsland.cpp)|Medium|
|687|[Longest Univalue Path](https://leetcode.com/problems/longest-univalue-path/) | [Python](./algorithms/python/LongestUnivaluePath/longestUnivaluePath.py)|Easy|
|684|[Redundant Connection](https://leetcode.com/problems/redundant-connection/) | [Python](./algorithms/python/RedundantConnection/findRedundantConnection.py)|Medium|
|674|[Longest Continuous Increasing Subsequence](https://leetcode.com/problems/longest-continuous-increasing-subsequence/) | [Python](./algorithms/python/LongestContinuousIncreasingSubsequence/findLengthOfLCIS.py)|Easy|
|671|[Second Minimum Node In a Binary Tree](https://leetcode.com/problems/second-minimum-node-in-a-binary-tree/) | [Python](./algorithms/python/SecondMinimumNodeInABinaryTree/findSecondMinimumValue.py)|Easy|
|665|[Non-decreasing Array](https://leetcode.com/problems/non-decreasing-array/) | [Python](./algorithms/python/Non-decreasingArray/checkPossibility.py)|Easy|
|662|[Maximum Width of Binary Tree](https://leetcode.com/problems/maximum-width-of-binary-tree/) | [Python](./algorithms/python/MaximumWidthOfBinaryTree/widthOfBinaryTree.py)|Medium|
|661|[Image Smoother](https://leetcode.com/problems/image-smoother/) | [Python](./algorithms/python/ImageSmoother/imageSmoother.py)|Easy|
|655|[Print Binary Tree](https://leetcode.com/problems/print-binary-tree/) | [Python](./algorithms/python/PrintBinaryTree/printTree.py)|Medium|
|652|[Find Duplicate Subtrees](https://leetcode.com/problems/find-duplicate-subtrees/) | [Python](./algorithms/python/FindDuplicateSubtrees/findDuplicateSubtrees.py)|Medium|
|647|[Palindromic Substrings](https://leetcode.com/problems/palindromic-substrings/) | [C++](./algorithms/cpp/palindromicSubstrings/PalindromicSubstrings.cpp)|Medium|
|643|[Maximum Average Subarray I](https://leetcode.com/problems/maximum-average-subarray-i/description/) | [C++](./algorithms/cpp/maximumAverageSubarray/MaximumAverageSubarray.I.cpp), [Python](./algorithms/python/MaximumAverageSubarrayI/findMaxAverage.py)|Easy|
|628|[Maximum Product of Three Numbers](https://leetcode.com/problems/maximum-product-of-three-numbers/) | [Python](./algorithms/python/MaximumProductOfThreeNumbers/maximumProduct.py)|Easy|
|623|[Add One Row to Tree](https://leetcode.com/problems/add-one-row-to-tree/) | [Python](./algorithms/python/AddOneRowToTree/addOneRow.py)|Medium|
|581|[Shortest Unsorted Continuous Subarray](https://leetcode.com/problems/shortest-unsorted-continuous-subarray/) | [Python](./algorithms/python/ShortestUnsortedContinuousSubarray/findUnsortedSubarray.py)|Easy|
|572|[Subtree of Another Tree](https://leetcode.com/problems/subtree-of-another-tree/) | [Python](./algorithms/python/SubtreeOfAnotherTree/isSubtree.py)|Easy|
|563|[Binary Tree Tilt](https://leetcode.com/problems/binary-tree-tilt/) | [Python](./algorithms/python/BinaryTreeTilt/findTilt.py)|Easy|
|547|[Friend Circles](https://leetcode.com/problems/friend-circles/) | [C++](./algorithms/cpp/friendCircles/FriendCircles.cpp)|Medium|
|543|[Diameter of Binary Tree](https://leetcode.com/problems/diameter-of-binary-tree/) | [Python](./algorithms/python/DiameterOfBinaryTree/diameterOfBinaryTree.py)|Easy|
|538|[Convert BST to Greater Tree](https://leetcode.com/problems/convert-bst-to-greater-tree/) | [Python](./algorithms/python/ConvertBSTtoGreaterTree/convertBST.py)|Easy|
|532|[K-diff Pairs in an Array](https://leetcode.com/problems/k-diff-pairs-in-an-array/) | [Python](./algorithms/python/K-diffPairsInAnArray/findPairs.py)|Easy|
|520|[Detect Capital](https://leetcode.com/problems/detect-capital/) | [C++](./algorithms/cpp/detectCapital/DetectCapital.cpp)|Easy|
|518|[Coin Change 2](https://leetcode.com/problems/coin-change-2/) | [C++](./algorithms/cpp/coinChange/CoinChange2.cpp)|Medium|
|509|[Fibonacci Number](https://leetcode.com/problems/fibonacci-number/) | [C++](./algorithms/cpp/fibonacciNumber/FibonacciNumber.cpp), [Python](./algorithms/python/FibonacciNumber/fib.py)|Easy|
|497|[Random Point in Non-overlapping Rectangles](https://leetcode.com/problems/random-point-in-non-overlapping-rectangles/) | [C++](./algorithms/cpp/randomPointInNonOverlappingRectangles/randomPointInNonOverlappingRectangles.cpp)|Medium|
|494|[Target Sum](https://leetcode.com/problems/target-sum/) | [C++](./algorithms/cpp/targetSum/targetSum.cpp)|Medium|
|477|[Total Hamming Distance](https://leetcode.com/problems/total-hamming-distance/) | [C++](./algorithms/cpp/totalHammingDistance/totalHammingDistance.cpp)|Medium|
|463|[Island Perimeter](https://leetcode.com/problems/island-perimeter/) | [C++](./algorithms/cpp/islandPerimeter/IslandPerimeter.cpp)|Easy|
|450|[DeleteNodeInABST](https://leetcode.com/problems/delete-node-in-a-bst/) | [Python](./algorithms/python/DeleteNodeInABST/deleteNode.py)|Medium|
|449|[Serialize and Deserialize BST](https://leetcode.com/problems/serialize-and-deserialize-bst/) | [Python](./algorithms/python/SerializeAndDeserializeBST/serialize.py)|Medium|
|438|[Find all Anagrams in a string](https://leetcode.com/problems/find-all-anagrams-in-a-string/) | [C++](./algorithms/cpp/findAllAnagramsInAString/Find-All-Anagrams-in-a-String.cpp)|Medium|
|437|[Path Sum III](https://leetcode.com/problems/path-sum-iii/) | [Python](./algorithms/python/PathSumIII/pathSum.py)|Medium|
|418|[SentenceScreenFitting](https://leetcode.com/problems/sentence-screen-fitting/) 🔒 | [C++](./algorithms/cpp/sentenceScreenFitting/sentenceScreenFitting.cpp)|Easy|
|416|[Partition Equal Subset Sum](https://leetcode.com/problems/partition-equal-subset-sum/description/) | [C++](./algorithms/cpp/partitionEqualSubsetSum/PartitionEqualSubsetSum.cpp)|Medium|
|415|[Add Strings](https://leetcode.com/problems/add-strings/) | [C++](./algorithms/cpp/addStrings/AddStrings.cpp)|Easy|
|414|[Third Maximum Number](https://leetcode.com/problems/third-maximum-number/) | [C++](./algorithms/cpp/thirdMaximumNumber/ThirdMaximumNumber.cpp), [Python](./algorithms/python/ThirdMaximumNumber/thirdMax.py)|Easy|
|413|[Arithmetic Slices](https://leetcode.com/problems/arithmetic-slices/) | [C++](./algorithms/cpp/arithmeticSlices/ArithmeticSlices.cpp)|Medium|
|412|[Fizz Buzz](https://leetcode.com/problems/fizz-buzz/) | [C++](./algorithms/cpp/fizzBuzz/FizzBuzz.cpp)|Easy|
|410|[Split Array Largest Sum](https://leetcode.com/problems/split-array-largest-sum/) | [C++](./algorithms/cpp/splitArrayLargestSum/SplitArrayLargestSum.cpp)|Hard|
|409|[Longest Palindrome](https://leetcode.com/problems/longest-palindrome/) | [C++](./algorithms/cpp/longestPalindrome/LongestPalindrome.cpp)|Easy|
|406|[Queue Reconstruction by Height](https://leetcode.com/problems/queue-reconstruction-by-height/) | [C++](./algorithms/cpp/queueReconstructionByHeight/QueueReconstructionByHeight.cpp)|Medium|
|405|[Convert a Number to Hexadecimal](https://leetcode.com/problems/convert-a-number-to-hexadecimal/) | [C++](./algorithms/cpp/convertANumberToHexadecimal/ConvertANumberToHexadecimal.cpp)|Easy|
|404|[Sum of Left Leaves](https://leetcode.com/problems/sum-of-left-leaves/) | [C++](./algorithms/cpp/sumOfLeftLeaves/SumOfLeftLeaves.cpp), [Python](./algorithms/python/SumOfLeftLeaves/sumOfLeftLeaves.py)|Easy|
|403|[Frog Jump](https://leetcode.com/problems/frog-jump/) | [C++](./algorithms/cpp/frogJump/FrogJump.cpp)|Hard|
|402|[Remove K Digits](https://leetcode.com/problems/remove-k-digits/) | [C++](./algorithms/cpp/removeKDigits/RemoveKDigits.cpp)|Medium|
|401|[Binary Watch](https://leetcode.com/problems/binary-watch/) | [C++](./algorithms/cpp/binaryWatch/BinaryWatch.cpp)|Easy|
|400|[Nth Digit](https://leetcode.com/problems/nth-digit/) | [C++](./algorithms/cpp/nthDigit/NthDigit.cpp)|Medium|
|399|[Evaluate Division](https://leetcode.com/problems/evaluate-division/) | [C++](./algorithms/cpp/evaluateDivision/EvaluateDivision.cpp)|Medium|
|398|[Random Pick Index](https://leetcode.com/problems/random-pick-index/) | [C++](./algorithms/cpp/randomPickIndex/RandomPickIndex.cpp)|Medium|
|397|[Integer Replacement](https://leetcode.com/problems/integer-replacement/) | [C++](./algorithms/cpp/integerReplacement/IntegerReplacement.cpp)|Medium|
|396|[Rotate Function](https://leetcode.com/problems/rotate-function/) | [C++](./algorithms/cpp/rotateFunction/RotateFunction.cpp)|Easy|
|395|[Longest Substring with At Least K Repeating Characters](https://leetcode.com/problems/longest-substring-with-at-least-k-repeating-characters/) | [C++](./algorithms/cpp/longestSubstringWithAtLeastKRepeatingCharacters/LongestSubstringWithAtLeastKRepeatingCharacters.cpp)|Medium|
|394|[Decode String](https://leetcode.com/problems/decode-string/) | [C++](./algorithms/cpp/decodeString/DecodeString.cpp)|Medium|
|393|[UTF-8 Validation](https://leetcode.com/problems/utf-8-validation/) | [C++](./algorithms/cpp/UTF8Validation/UTF8Validation.cpp)|Medium|
|392|[Is Subsequence](https://leetcode.com/problems/is-subsequence/) | [C++](./algorithms/cpp/isSubsequence/IsSubsequence.cpp)|Medium|
|391|[Perfect Rectangle](https://leetcode.com/problems/perfect-rectangle/) | [C++](./algorithms/cpp/perfectRectangle/PerfectRectangle.cpp)|Hard|
|390|[Elimination Game](https://leetcode.com/problems/elimination-game/) | [C++](./algorithms/cpp/eliminationGame/EliminationGame.cpp)|Medium|
|389|[Find the Difference](https://leetcode.com/problems/find-the-difference/) | [C++](./algorithms/cpp/findTheDifference/FindTheDifference.cpp)|Easy|
|388|[Longest Absolute File Path](https://leetcode.com/problems/longest-absolute-file-path/) | [C++](./algorithms/cpp/longestAbsoluteFilePath/LongestAbsoluteFilePath.cpp)|Medium|
|387|[First Unique Character in a String](https://leetcode.com/problems/first-unique-character-in-a-string/) | [C++](./algorithms/cpp/firstUniqueCharacterInAString/FirstUniqueCharacterInAString.cpp)|Easy|
|386|[Lexicographical Numbers](https://leetcode.com/problems/lexicographical-numbers/) | [C++](./algorithms/cpp/lexicographicalNumbers/LexicographicalNumbers.cpp)|Medium|
|385|[Mini Parser](https://leetcode.com/problems/mini-parser/) | [C++](./algorithms/cpp/miniParser/MiniParser.cpp)|Medium|
|384|[Shuffle an Array](https://leetcode.com/problems/shuffle-an-array/) | [C++](./algorithms/cpp/shuffleAnArray/ShuffleAnArray.cpp)|Medium|
|383|[Ransom Note](https://leetcode.com/problems/ransom-note/) | [C++](./algorithms/cpp/ransomNote/RansomNote.cpp)|Easy|
|382|[Linked List Random Node](https://leetcode.com/problems/linked-list-random-node/) | [C++](./algorithms/cpp/linkedListRandomNode/LinkedListRandomNode.cpp)|Medium|
|381|[Insert Delete GetRandom O(1) - Duplicates allowed](https://leetcode.com/problems/insert-delete-getrandom-o1-duplicates-allowed/) | [C++](./algorithms/cpp/insertDeleteGetRandom/InsertDeleteGetrandomO1DuplicatesAllowed.cpp)|Hard|
|380|[Insert Delete GetRandom O(1)](https://leetcode.com/problems/insert-delete-getrandom-o1/) | [C++](./algorithms/cpp/insertDeleteGetRandom/InsertDeleteGetrandomO1.cpp)|Hard|
|377|[Combination Sum IV](https://leetcode.com/problems/combination-sum-iv/) | [C++](./algorithms/cpp/combinationSumIV/combinationSumIV.cpp)|Medium|
|376|[Wiggle Subsequence](https://leetcode.com/problems/wiggle-subsequence/) | [C++](./algorithms/cpp/wiggleSubsequence/wiggleSubsequence.cpp)|Medium|
|371|[Sum of Two Integers](https://leetcode.com/problems/sum-of-two-integers/description/) | [C++](./algorithms/cpp/sumOfTwoIntegers/SumOfTwoIntegers.cpp)|Easy|
|367|[Valid Perfect Square](https://leetcode.com/problems/valid-perfect-square/description/) | [C++](./algorithms/cpp/validPerfectSquare/ValidPerfectSquare.cpp)|Easy|
|357|[Count Numbers with Unique Digits](https://leetcode.com/problems/count-numbers-with-unique-digits/) | [C++](./algorithms/cpp/countNumbersWithUniqueDigits/CountNumbersWithUniqueDigits.cpp)|Medium|
|350|[Intersection of Two Arrays II](https://leetcode.com/problems/intersection-of-two-arrays-ii/) | [C++](./algorithms/cpp/intersectionOfTwoArrays/intersectionOfTwoArraysII.cpp)|Easy|
|349|[Intersection of Two Arrays](https://leetcode.com/problems/intersection-of-two-arrays/) | [C++](./algorithms/cpp/intersectionOfTwoArrays/intersectionOfTwoArrays.cpp)|Easy|
|347|[Top K Frequent Elements](https://leetcode.com/problems/top-k-frequent-elements/) | [C++](./algorithms/cpp/topKFrequentElements/topKFrequentElements.cpp)|Medium|
|345|[Reverse Vowels of a String](https://leetcode.com/problems/reverse-vowels-of-a-string/) | [C++](./algorithms/cpp/reverseVowelsOfAString/reverseVowelsOfAString.cpp)|Easy|
|344|[Reverse String](https://leetcode.com/problems/reverse-string/) | [C++](./algorithms/cpp/reverseString/ReverseString.cpp)|Easy|
|343|[Integer Break](https://leetcode.com/problems/integer-break/) | [C++](./algorithms/cpp/integerBreak/IntegerBreak.cpp)|Medium|
|342|[Power of Four](https://leetcode.com/problems/power-of-four/) | [C++](./algorithms/cpp/powerOfFour/PowerOfFour.cpp)|Easy|
|341|[Flatten Nested List Iterator](https://leetcode.com/problems/flatten-nested-list-iterator/) | [C++](./algorithms/cpp/flattenNestedListIterator/FlattenNestedListIterator.cpp)|Medium|
|338|[Counting Bits](https://leetcode.com/problems/counting-bits/) | [C++](./algorithms/cpp/countingBits/CountingBits.cpp)|Medium|
|337|[House Robber III](https://leetcode.com/problems/house-robber-iii/) | [C++](./algorithms/cpp/houseRobber/houseRobberIII.cpp), [Python](./algorithms/python/HouseRobberIII/rob.py)|Medium|
|336|[Palindrome Pairs](https://leetcode.com/problems/palindrome-pairs/) | [C++](./algorithms/cpp/palindromePairs/PalindromePairs.cpp)|Hard|
|334|[Increasing Triplet Subsequence](https://leetcode.com/problems/increasing-triplet-subsequence/) | [C++](./algorithms/cpp/increasingTripletSubsequence/increasingTripletSubsequence.cpp)|Medium|
|332|[Reconstruct Itinerary](https://leetcode.com/problems/reconstruct-itinerary/) | [C++](./algorithms/cpp/reconstructItinerary/ReconstructItinerary.cpp)|Medium|
|331|[Verify Preorder Serialization of a Binary Tree](https://leetcode.com/problems/verify-preorder-serialization-of-a-binary-tree/) | [C++](./algorithms/cpp/verifyPreorderSerializationOfABinaryTree/VerifyPreorderSerializationOfABinaryTree.cpp)|Medium|
|330|[Patching Array](https://leetcode.com/problems/patching-array/) | [C++](./algorithms/cpp/patchingArray/PatchingArray.cpp)|Medium|
|329|[Longest Increasing Path in a Matrix](https://leetcode.com/problems/longest-increasing-path-in-a-matrix/) | [C++](./algorithms/cpp/longestIncreasingPathInAMatrix/LongestIncreasingPathInAMatrix.cpp)|Medium|
|328|[Odd Even Linked List](https://leetcode.com/problems/odd-even-linked-list/) | [C++](./algorithms/cpp/oddEvenLinkedList/OddEvenLinkedList.cpp)|Easy|
|327|[Count of Range Sum](https://leetcode.com/problems/count-of-range-sum/) | [C++](./algorithms/cpp/countOfRangeSum/CountOfRangeSum.cpp)|Hard|
|326|[Power of Three](https://leetcode.com/problems/power-of-three/) | [C++](./algorithms/cpp/powerOfThree/PowerOfThree.cpp)|Easy|
|324|[Wiggle Sort II](https://leetcode.com/problems/wiggle-sort-ii/) | [C++](./algorithms/cpp/wiggleSort/WiggleSort.II.cpp)|Medium|
|322|[Coin Change](https://leetcode.com/problems/coin-change/) | [C++](./algorithms/cpp/coinChange/coinChange.cpp)|Medium|
|321|[Create Maximum Number](https://leetcode.com/problems/create-maximum-number/) | [C++](./algorithms/cpp/createMaximumNumber/CreateMaximumNumber.cpp)|Hard|
|319|[Bulb Switcher](https://leetcode.com/problems/bulb-switcher/) | [C++](./algorithms/cpp/bulbSwitcher/bulbSwitcher.cpp)|Medium|
|318|[Maximum Product of Word Lengths](https://leetcode.com/problems/maximum-product-of-word-lengths/) | [C++](./algorithms/cpp/maximumProductOfWordLengths/MaximumProductOfWordLengths.cpp)|Medium|
|316|[Remove Duplicate Letters](https://leetcode.com/problems/remove-duplicate-letters/) | [C++](./algorithms/cpp/removeDuplicateLetters/RemoveDuplicateLetters.cpp)|Hard|
|315|[Count of Smaller Numbers After Self](https://leetcode.com/problems/count-of-smaller-numbers-after-self/) | [C++](./algorithms/cpp/countOfSmallerNumbersAfterSelf/countOfSmallerNumbersAfterSelf.cpp)|Hard|
|313|[Super Ugly Number](https://leetcode.com/problems/super-ugly-number/) | [C++](./algorithms/cpp/superUglyNumber/SuperUglyNumber.cpp)|Medium|
|312|[Burst Balloons](https://leetcode.com/problems/burst-balloons/) | [C++](./algorithms/cpp/burstBalloons/BurstBalloons.cpp)|Hard|
|310|[Minimum Height Trees](https://leetcode.com/problems/minimum-height-trees/) | [C++](./algorithms/cpp/minimumHeightTrees/MinimumHeightTrees.cpp)|Medium|
|309|[Best Time to Buy and Sell Stock with Cooldown](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-with-cooldown/) | [C++](./algorithms/cpp/bestTimeToBuyAndSellStock/BestTimeToBuyAndSellStockWithCooldown.cpp)|Medium|
|307|[Range Sum Query - Mutable](https://leetcode.com/problems/range-sum-query-mutable/) | [C++](./algorithms/cpp/rangeSumQuery-Immutable/rangeSumQuery-Mutable/RangeSumQueryMutable.cpp)|Medium|
|306|[Additive Number](https://leetcode.com/problems/additive-number/) | [C++](./algorithms/cpp/additiveNumber/AdditiveNumber.cpp)|Medium|
|304|[Range Sum Query 2D - Immutable](https://leetcode.com/problems/range-sum-query-2d-immutable/) | [C++](./algorithms/cpp/rangeSumQuery2D-Immutable/RangeSumQuery2dImmutable.cpp)|Medium|
|303|[Range Sum Query - Immutable](https://leetcode.com/problems/range-sum-query-immutable/)  | [C++](./algorithms/cpp/rangeSumQuery-Immutable/rangeSumQuery-Immutable.cpp)|Easy|
|301|[Remove Invalid Parentheses](https://leetcode.com/problems/remove-invalid-parentheses/) | [C++](./algorithms/cpp/removeInvalidParentheses/RemoveInvalidParentheses.cpp) |Hard|
|300|[Longest Increasing Subsequence](https://leetcode.com/problems/longest-increasing-subsequence/)  | [C++](./algorithms/cpp/longestIncreasingSubsequence/longestIncreasingSubsequence.cpp)|Medium|
|299|[Bulls and Cows](https://leetcode.com/problems/bulls-and-cows/)  | [C++](./algorithms/cpp/bullsAndCows/bullsAndCows.cpp)|Easy|
|297|[Serialize and Deserialize Binary Tree](https://leetcode.com/problems/serialize-and-deserialize-binary-tree/)  | [C++](./algorithms/cpp/serializeAndDeserializeBinaryTree/SerializeAndDeserializeBinaryTree.cpp)|Medium|
|295|[Find Median from Data Stream](https://leetcode.com/problems/find-median-from-data-stream/) | [C++](./algorithms/cpp/findMedianFromDataStream/FindMedianFromDataStream.cpp)|Hard|
|292|[Nim Game](https://leetcode.com/problems/nim-game/)  | [C++](./algorithms/cpp/nimGame/nimGame.cpp)|Easy|
|290|[Word Pattern](https://leetcode.com/problems/word-pattern/) | [C++](./algorithms/cpp/wordPattern/WordPattern.cpp)|Easy|
|289|[Game of Life](https://leetcode.com/problems/game-of-life/) | [C++](./algorithms/cpp/gameOfLife/GameOfLife.cpp)|Medium|
|287|[Find the Duplicate Number](https://leetcode.com/problems/find-the-duplicate-number/)  | [C++](./algorithms/cpp/findTheDuplicateNumber/findTheDuplicateNumber.cpp), [Python](./algorithms/python/FindTheDuplicateNumber/findDuplicate.py)|Hard|
|285|[Inorder Successor in BST](https://leetcode.com/problems/inorder-successor-in-bst/) 🔒 | [Java](./algorithms/java/src/inorderSuccessorInBST/inorderSuccessorInBST.java)|Medium|
|284|[Peeking Iterator](https://leetcode.com/problems/peeking-iterator/)  | [C++](./algorithms/cpp/peekingIterator/PeekingIterator.cpp)|Medium|
|283|[Move Zeroes](https://leetcode.com/problems/move-zeroes/)  | [C++](./algorithms/cpp/moveZeroes/moveZeroes.cpp)|Easy|
|282|[Expression Add Operators](https://leetcode.com/problems/expression-add-operators/)  | [C++](./algorithms/cpp/expressionAddOperators/ExpressionAddOperators.cpp)|Hard|
|279|[Perfect Squares](https://leetcode.com/problems/perfect-squares/) | [C++](./algorithms/cpp/perfectSquares/PerfectSquares.cpp)|Medium|
|278|[First Bad Version](https://leetcode.com/problems/first-bad-version/)| [C++](./algorithms/cpp/firstBadVersion/FirstBadVersion.cpp), [Java](./algorithms/java/src/firstBadVersion/firstBadVersion.java)|Easy|
|275|[H-Index II](https://leetcode.com/problems/h-index-ii/)| [C++](./algorithms/cpp/h-Index/h-Index.II.cpp)|Medium|
|274|[H-Index](https://leetcode.com/problems/h-index/)| [C++](./algorithms/cpp/h-Index/h-Index.cpp)|Medium|
|273|[Integer to English Words](https://leetcode.com/problems/integer-to-english-words/)| [C++](./algorithms/cpp/integerToEnglishWords/IntegerToEnglishWords.cpp)|Medium|
|268|[Missing Number](https://leetcode.com/problems/missing-number/)| [C++](./algorithms/cpp/missingNumber/MissingNumber.cpp)|Medium|
|264|[Ugly Number II](https://leetcode.com/problems/ugly-number-ii/)| [C++](./algorithms/cpp/uglyNumber/UglyNumber.II.cpp)|Medium|
|263|[Ugly Number](https://leetcode.com/problems/ugly-number/)| [C++](./algorithms/cpp/uglyNumber/UglyNumber.cpp)|Easy|
|260|[Single Number III](https://leetcode.com/problems/single-number-iii/)| [C++](./algorithms/cpp/singleNumber/singleNumber.III.cpp)|Medium|
|258|[Add Digits](https://leetcode.com/problems/add-digits/)| [C++](./algorithms/cpp/addDigits/addDigits.cpp)|Easy|
|257|[Binary Tree Paths](https://leetcode.com/problems/binary-tree-paths/)| [C++](./algorithms/cpp/binaryTreePaths/binaryTreePaths.cpp)|Easy|
|242|[Valid Anagram](https://leetcode.com/problems/valid-anagram/)| [C++](./algorithms/cpp/anagrams/ValidAnagram.cpp), [Java](./algorithms/java/src/validAnagram/ValidAnagram.java)|Easy|
|241|[Different Ways to Add Parentheses](https://leetcode.com/problems/different-ways-to-add-parentheses/)|[C++](./algorithms/cpp/differentWaysToAddParentheses/DifferentWaysToAddParentheses.cpp), [Python](./algorithms/python/DifferentWaysToAddParentheses/diffWaysToCompute.py)|Medium|
|240|[Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii/)|[C++](./algorithms/cpp/search2DMatrix/search2DMatrix.II.cpp), [Java](./algorithms/java/src/searchA2DMatrixII/SearchA2DMatrixII.java), [Python](./algorithms/python/SearchA2DMatrixII/searchMatrix.py)|Medium|
|239|[Sliding Window Maximum](https://leetcode.com/problems/sliding-window-maximum/)| [C++](./algorithms/cpp/slidingWindowMaximum/SlidingWindowMaximum.cpp)|Hard|
|238|[Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self/)| [C++](./algorithms/cpp/productOfArrayExceptSelf/ProductOfArrayExceptSelf.cpp)|Medium|
|237|[Delete Node in a Linked List](https://leetcode.com/problems/delete-node-in-a-linked-list/)| [C++](./algorithms/cpp/deleteNodeInALinkedList/DeleteNodeInALinkedList.cpp)|Easy|
|236|[Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/)| [C++](./algorithms/cpp/lowestCommonAncestorOfABinaryTree/LowestCommonAncestorOfABinaryTree.cpp), [Java](./algorithms/java/src/lowestCommonAncestorOfABinaryTree/lowestCommonAncestorOfABinaryTree.java), [Python](./algorithms/python/LowestCommonAncestorOfABinaryTree/lowestCommonAncestor.py)|Medium|
|235|[Lowest Common Ancestor of a Binary Search Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree/)| [C++](./algorithms/cpp/lowestCommonAncestorOfABinarySearchTree/LowestCommonAncestorOfABinarySearchTree.cpp), [Python](./algorithms/python/LowestCommonAncestorOfABinarySearchTree/lowestCommonAncestor.py)|Easy|
|234|[Palindrome Linked List](https://leetcode.com/problems/palindrome-linked-list/)| [C++](./algorithms/cpp/palindromeLinkedList/PalindromeLinkedList.cpp)|Easy|
|233|[Number of Digit One](https://leetcode.com/problems/number-of-digit-one/)| [C++](./algorithms/cpp/numberOfDigitOne/NumberOfDigitOne.cpp)|Medium|
|232|[Implement Queue using Stacks](https://leetcode.com/problems/implement-queue-using-stacks/)| [C++](./algorithms/cpp/implementQueueUsingStacks/ImplementQueueUsingStacks.cpp), [Java](./algorithms/java/src/myQueue/MyQueue.java)|Easy|
|231|[Power of Two](https://leetcode.com/problems/power-of-two/)| [C++](./algorithms/cpp/powerOfTwo/PowerOfTwo.cpp)|Easy|
|230|[Kth Smallest Element in a BST](https://leetcode.com/problems/kth-smallest-element-in-a-bst/)| [C++](./algorithms/cpp/kthSmallestElementInaBST/KthSmallestElementInABst.cpp), [Python](./algorithms/python/KthSmallestElementInABST/kthSmallest.py)|Medium|
|229|[Majority Element II](https://leetcode.com/problems/majority-element-ii/) | [C++](./algorithms/cpp/majorityElement/majorityElement.II.cpp)|Medium|
|228|[Summary Ranges](https://leetcode.com/problems/summary-ranges/)| [C++](./algorithms/cpp/summaryRanges/SummaryRanges.cpp)|Easy|
|227|[Basic Calculator II](https://leetcode.com/problems/basic-calculator-ii/)| [C++](./algorithms/cpp/basicCalculator/BasicCalculator.II.cpp)|Medium|
|226|[Invert Binary Tree](https://leetcode.com/problems/invert-binary-tree/)| [C++](./algorithms/cpp/invertBinaryTree/InvertBinaryTree.cpp)|Easy|
|225|[Implement Stack using Queues](https://leetcode.com/problems/implement-stack-using-queues/)| [C++](./algorithms/cpp/implementStackUsingQueues/ImplementStackUsingQueues.cpp), [Java](./algorithms/java/src/myStack/MyStack.java)|Medium|
|224|[Basic Calculator](https://leetcode.com/problems/basic-calculator/)| [C++](./algorithms/cpp/basicCalculator/BasicCalculator.cpp)|Medium|
|223|[Rectangle Area](https://leetcode.com/problems/rectangle-area/)| [C++](./algorithms/cpp/rectangleArea/RectangleArea.cpp)|Easy|
|222|[Count Complete Tree Nodes](https://leetcode.com/problems/count-complete-tree-nodes/)| [C++](./algorithms/cpp/countCompleteTreeNodes/CountCompleteTreeNodes.cpp), [Python](./algorithms/python/CountCompleteTreeNodes/countNodes.py)|Medium|
|221|[Maximal Square](https://leetcode.com/problems/maximal-square/)| [C++](./algorithms/cpp/maximalSquare/MaximalSquare.cpp)|Medium|
|220|[Contains Duplicate III](https://leetcode.com/problems/contains-duplicate-iii/)| [C++](./algorithms/cpp/containsDuplicate/ContainsDuplicate.III.cpp), [Python](./algorithms/python/ContainsDuplicateIII/containsNearbyAlmostDuplicate.py)|Medium|
|219|[Contains Duplicate II](https://leetcode.com/problems/contains-duplicate-ii/)| [C++](./algorithms/cpp/containsDuplicate/ContainsDuplicate.II.cpp), [Python](./algorithms/python/ContainsDuplicateII/containsNearbyDuplicate.py)|Easy|
|218|[The Skyline Problem](https://leetcode.com/problems/the-skyline-problem/)| [C++](./algorithms/cpp/theSkylineProblem/TheSkylineProblem.cpp)|Hard|
|217|[Contains Duplicate](https://leetcode.com/problems/contains-duplicate/)| [C++](./algorithms/cpp/containsDuplicate/ContainsDuplicate.cpp)|Easy|
|216|[Combination Sum III](https://leetcode.com/problems/combination-sum-iii/)| [C++](./algorithms/cpp/combinationSum/combinationSum.III.cpp)|Medium|
|215|[Kth Largest Element in an Array](https://leetcode.com/problems/kth-largest-element-in-an-array/)| [C++](./algorithms/cpp/kthLargestElementInAnArray/KthLargestElementInAnArray.cpp)|Medium|
|214|[Shortest Palindrome](https://leetcode.com/problems/shortest-palindrome/)| [C++](./algorithms/cpp/shortestPalindrome/ShortestPalindrome.cpp)|Hard|
|213|[House Robber II](https://leetcode.com/problems/house-robber-ii/)| [C++](./algorithms/cpp/houseRobber/houseRobber.II.cpp)|Medium|
|212|[Word Search II](https://leetcode.com/problems/word-search-ii/)| [C++](./algorithms/cpp/wordSearch/wordSearch.II.cpp)|Hard|
|211|[Add and Search Word - Data structure design](https://leetcode.com/problems/add-and-search-word-data-structure-design/)| [C++](./algorithms/cpp/addAndSearchWord/AddAndSearchWord.cpp)|Medium|
|210|[Course Schedule II](https://leetcode.com/problems/course-schedule-ii/)| [C++](./algorithms/cpp/courseSchedule/CourseSchedule.II.cpp)|Medium|
|209|[Minimum Size Subarray Sum](https://leetcode.com/problems/minimum-size-subarray-sum/)| [C++](./algorithms/cpp/minimumSizeSubarraySum/MinimumSizeSubarraySum.cpp)|Medium|
|208|[Implement Trie (Prefix Tree)](https://leetcode.com/problems/implement-trie-prefix-tree/)| [C++](./algorithms/cpp/implementTriePrefixTree/ImplementTriePrefixTree.cpp)|Medium|
|207|[Course Schedule](https://leetcode.com/problems/course-schedule/)| [C++](./algorithms/cpp/courseSchedule/CourseSchedule.cpp)|Medium|
|206|[Reverse Linked List](https://leetcode.com/problems/reverse-linked-list/)| [C++](./algorithms/cpp/reverseLinkedList/reverseLinkedList.cpp), [Java](./algorithms/java/src/reverseLinkedList/ReverseLinkedList.java)|Easy|
|205|[Isomorphic Strings](https://leetcode.com/problems/isomorphic-strings/)| [C++](./algorithms/cpp/isomorphicStrings/IsomorphicStrings.cpp)|Easy|
|204|[Count Primes](https://leetcode.com/problems/count-primes/)| [C++](./algorithms/cpp/countPrimes/CountPrimes.cpp)|Easy|
|203|[Remove Linked List Elements](https://leetcode.com/problems/remove-linked-list-elements/)| [C++](./algorithms/cpp/removeLinkedListElements/RemoveLinkedListElements.cpp)|Easy|
|202|[Happy Number](https://leetcode.com/problems/happy-number/)| [C++](./algorithms/cpp/happyNumber/HappyNumber.cpp), [Python](./algorithms/python/HappyNumber/isHappy.py)|Easy|
|201|[Bitwise AND of Numbers Range](https://leetcode.com/problems/bitwise-and-of-numbers-range/)| [C++](./algorithms/cpp/bitwiseANDOfNumbersRange/BitwiseAndOfNumbersRange.cpp)|Medium|
|200|[Number of Islands](https://leetcode.com/problems/number-of-islands/)| [C++](./algorithms/cpp/numberOfIslands/NumberOfIslands.cpp), [Python](./algorithms/python/NumberOfIslands/numIslands.py)|Medium|
|199|[Binary Tree Right Side View](https://leetcode.com/problems/binary-tree-right-side-view/)| [C++](./algorithms/cpp/binaryTreeRightSideView/binaryTreeRightSideView.cpp)|Medium|
|198|[House Robber](https://leetcode.com/problems/house-robber/)| [C++](./algorithms/cpp/houseRobber/houseRobber.cpp), [Python](./algorithms/python/HouseRobber/rob.py)|Easy|
|191|[Number of 1 Bits](https://leetcode.com/problems/number-of-1-bits/)| [C++](./algorithms/cpp/numberOf1Bits/numberOf1Bits.cpp)|Easy|
|190|[Reverse Bits](https://leetcode.com/problems/reverse-bits/)| [C++](./algorithms/cpp/reverseBits/reverseBits.cpp)|Easy|
|189|[Rotate Array](https://leetcode.com/problems/rotate-array/)| [C++](./algorithms/cpp/rotateArray/rotateArray.cpp), [Java](./algorithms/java/src/rotateArray/RotateArray.java)|Easy|
|188|[Best Time to Buy and Sell Stock IV](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iv/)| [C++](./algorithms/cpp/bestTimeToBuyAndSellStock/bestTimeToBuyAndSellStock.IV.cpp)|Hard|
|187|[Repeated DNA Sequences](https://leetcode.com/problems/repeated-dna-sequences/)| [C++](./algorithms/cpp/repeatedDNASequences/repeatedDNASequences.cpp)|Medium|
|186|[Reverse Words in a String II](https://leetcode.com/problems/reverse-words-in-a-string-ii/) 🔒 | [C++](./algorithms/cpp/reverseWordsInAString/reverseWordsInAString.II.cpp)|Medium|
|179|[Largest Number](https://leetcode.com/problems/largest-number/) | [C++](./algorithms/cpp/largestNumber/largestNumber.cpp)|Medium|
|174|[Dungeon Game](https://leetcode.com/problems/dungeon-game/) | [C++](./algorithms/cpp/dungeonGame/dungeonGame.cpp)|Hard|
|173|[Binary Search Tree Iterator](https://leetcode.com/problems/binary-search-tree-iterator/) | [C++](./algorithms/cpp/binarySearchTreeIterator/binarySearchTreeIterator.cpp), [Java](./algorithms/java/src/binarySearchTreeIterator/binarySearchTreeIterator.java), [Python](./algorithms/python/BinarySearchTreeIterator/BSTIterator.py)|Medium|
|172|[Factorial Trailing Zeroes](https://leetcode.com/problems/factorial-trailing-zeroes/) | [C++](./algorithms/cpp/factorialTrailingZeroes/factorialTrailingZeroes.cpp)|Easy|
|171|[Excel Sheet Column Number](https://leetcode.com/problems/excel-sheet-column-number/) | [C++](./algorithms/cpp/excelSheetColumnNumber/excelSheetColumnNumber.cpp)|Easy|
|170|[Two Sum III - Data structure design](https://leetcode.com/problems/two-sum-iii-data-structure-design/) 🔒 | [C++](./algorithms/cpp/twoSum/twoSum.III.cpp)|Easy|
|169|[Majority Element](https://leetcode.com/problems/majority-element/) | [C++](./algorithms/cpp/majorityElement/majorityElement.cpp)|Easy|
|168|[Excel Sheet Column Title](https://leetcode.com/problems/excel-sheet-column-title/) | [C++](./algorithms/cpp/excelSheetColumnTitle/excelSheetColumnTitle.cpp)|Easy|
|167|[Two Sum II - Input array is sorted](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/) 🔒 | [C++](./algorithms/cpp/twoSum/twoSum.II.cpp)|Medium|
|166|[Fraction to Recurring Decimal](https://leetcode.com/problems/fraction-to-recurring-decimal/) | [C++](./algorithms/cpp/fractionToRecurringDecimal/fractionToRecurringDecimal.cpp)|Medium|
|165|[Compare Version Numbers](https://leetcode.com/problems/compare-version-numbers/) | [C++](./algorithms/cpp/compareVersionNumbers/compareVersionNumbers.cpp)|Easy|
|164|[Maximum Gap](https://leetcode.com/problems/maximum-gap/) | [C++](./algorithms/cpp/maximumGap/maximumGap.cpp)|Hard|
|163|[Missing Ranges](https://leetcode.com/problems/missing-ranges/) 🔒 | [C++](./algorithms/cpp/missingRanges/missingRanges.cpp)|Medium|
|162|[Find Peak Element](https://leetcode.com/problems/find-peak-element/) | [C++](./algorithms/cpp/findPeakElement/findPeakElement.cpp), [Java](./algorithms/java/src/findPeakElement/findPeakElement.java)|Medium|
|161|[One Edit Distance](https://leetcode.com/problems/one-edit-distance/)🔒 | [C++](./algorithms/cpp/oneEditDistance/oneEditDistance.cpp)|Medium|
|160|[Intersection of Two Linked Lists](https://leetcode.com/problems/intersection-of-two-linked-lists/) | [C++](./algorithms/cpp/intersectionOfTwoLinkedLists/intersectionOfTwoLinkedLists.cpp)|Easy|
|159|[Longest Substring with At Most Two Distinct Characters](https://leetcode.com/problems/longest-substring-with-at-most-two-distinct-characters/) 🔒 | [C++](./algorithms/cpp/longestSubstringWithAtMostTwoDistinctCharacters/longestSubstringWithAtMostTwoDistinctCharacters.cpp)|Hard|
|158|[Read N Characters Given Read4 II - Call multiple times](https://leetcode.com/problems/read-n-characters-given-read4-ii-call-multiple-times/) 🔒 | [C++](./algorithms/cpp/readNCharactersGivenRead4/readNCharactersGivenRead4.II.cpp)|Hard|
|157|[Read N Characters Given Read4](https://leetcode.com/problems/read-n-characters-given-read4/) 🔒 | [C++](./algorithms/cpp/readNCharactersGivenRead4/readNCharactersGivenRead4.cpp)|Easy|
|156|[Binary Tree Upside Down](https://leetcode.com/problems/binary-tree-upside-down/) 🔒 | [C++](./algorithms/cpp/binaryTreeUpsideDown/binaryTreeUpsideDown.cpp)|Medium|
|155|[Min Stack](https://leetcode.com/problems/min-stack/)| [C++](./algorithms/cpp/minStack/minStack.cpp), [Java](./algorithms/java/src/minStack/MinStack.java)|Easy|
|154|[Find Minimum in Rotated Sorted Array II](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array-ii/)| [C++](./algorithms/cpp/findMinimumInRotatedSortedArray/findMinimumInRotatedSortedArray.II.cpp)|Hard|
|153|[Find Minimum in Rotated Sorted Array](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array/)| [C++](./algorithms/cpp/findMinimumInRotatedSortedArray/findMinimumInRotatedSortedArray.cpp), [Java](./algorithms/java/src/findMinimumInRotatedSortedArray/findMinimumInRotatedSortedArray.java)|Medium|
|152|[Maximum Product Subarray](https://leetcode.com/problems/maximum-product-subarray/)| [C++](./algorithms/cpp/maximumProductSubarray/maximumProductSubarray.cpp)|Medium|
|151|[Reverse Words in a String](https://leetcode.com/problems/reverse-words-in-a-string/)| [C++](./algorithms/cpp/reverseWordsInAString/reverseWordsInAString.cpp), [Java](./algorithms/java/src/reverseWordsInAString/ReverseWordsInAString.java)|Medium|
|150|[Evaluate Reverse Polish Notation](https://leetcode.com/problems/evaluate-reverse-polish-notation/)| [C++](./algorithms/cpp/evaluateReversePolishNotation/evaluateReversePolishNotation.cpp)|Medium|
|149|[Max Points on a Line](https://leetcode.com/problems/max-points-on-a-line/)| [C++](./algorithms/cpp/maxPointsOnALine/maxPointsOnALine.cpp)|Hard|
|148|[Sort List](https://leetcode.com/problems/sort-list/)| [C++](./algorithms/cpp/sortList/sortList.cpp), [Python](./algorithms/python/SortList/sortList.py)|Medium|
|147|[Insertion Sort List](https://leetcode.com/problems/insertion-sort-list/)| [C++](./algorithms/cpp/insertionSortList/insertionSortList.cpp), [Python](./algorithms/python/InsertionSortList/insertionSortList.py)|Medium|
|146|[LRU Cache](https://leetcode.com/problems/lru-cache/)| [C++](./algorithms/cpp/LRUCache/LRUCache.cpp), [Java](./algorithms/java/src/lruCache/LRUCache.java)|Hard|
|145|[Binary Tree Postorder Traversal](https://leetcode.com/problems/binary-tree-postorder-traversal/)| [C++](./algorithms/cpp/binaryTreePostorderTraversal/binaryTreePostorderTraversal.cpp), [Python](./algorithms/python/BinaryTreePostorderTraversal/postorderTraversal.py)|Hard|
|144|[Binary Tree Preorder Traversal](https://leetcode.com/problems/binary-tree-preorder-traversal/)| [C++](./algorithms/cpp/binaryTreePreorderTraversal/binaryTreePreorderTraversal.cpp), [Java](./algorithms/java/src/binaryTreePreorderTraversal/binaryTreePreorderTraversal.java)|Medium|
|143|[Reorder List](https://leetcode.com/problems/reorder-list/)| [C++](./algorithms/cpp/reorderList/reorderList.cpp), [Python](./algorithms/python/ReorderList/reorderList.py)|Medium|
|142|[Linked List Cycle II](https://leetcode.com/problems/linked-list-cycle-ii/)| [C++](./algorithms/cpp/linkedListCycle/linkedListCycle.II.cpp), [Python](./algorithms/python/LinkedListCycleII/detectCycle.py)|Medium|
|141|[Linked List Cycle](https://leetcode.com/problems/linked-list-cycle/)| [C++](./algorithms/cpp/linkedListCycle/linkedListCycle.cpp)|Medium|
|140|[Word Break II](https://leetcode.com/problems/word-break-ii/)| [C++](./algorithms/cpp/wordBreak/wordBreak.II.cpp)|Hard|
|139|[Word Break](https://leetcode.com/problems/word-break/)| [C++](./algorithms/cpp/wordBreak/wordBreak.cpp)|Medium|
|138|[Copy List with Random Pointer](https://leetcode.com/problems/copy-list-with-random-pointer/)| [C++](./algorithms/cpp/copyListWithRandomPointer/copyListWithRandomPointer.cpp), [Python](./algorithms/python/CopyListWithRandomPointer/copyRandomList.py)|Hard|
|137|[Single Number II](https://leetcode.com/problems/single-number-ii/)| [C++](./algorithms/cpp/singleNumber/singleNumber.II.cpp)|Medium|
|136|[Single Number](https://leetcode.com/problems/single-number/)| [C++](./algorithms/cpp/singleNumber/singleNumber.cpp)|Medium|
|135|[Candy](https://leetcode.com/problems/candy/)| [C++](./algorithms/cpp/candy/candy.cpp)|Hard|
|134|[Gas Station](https://leetcode.com/problems/gas-station/)| [C++](./algorithms/cpp/gasStation/gasStation.cpp)|Medium|
|133|[Clone Graph](https://leetcode.com/problems/clone-graph/)| [C++](./algorithms/cpp/cloneGraph/cloneGraph.cpp)|Medium|
|132|[Palindrome Partitioning II](https://leetcode.com/problems/palindrome-partitioning-ii/)| [C++](./algorithms/cpp/palindromePartitioning/palindromePartitioning.II.cpp)|Hard|
|131|[Palindrome Partitioning](https://leetcode.com/problems/palindrome-partitioning/)| [C++](./algorithms/cpp/palindromePartitioning/palindromePartitioning.cpp)|Medium|
|130|[Surrounded Regions](https://leetcode.com/problems/surrounded-regions/)| [C++](./algorithms/cpp/surroundedRegions/surroundedRegions.cpp)|Medium|
|129|[Sum Root to Leaf Numbers](https://leetcode.com/problems/sum-root-to-leaf-numbers/)| [C++](./algorithms/cpp/sumRootToLeafNumber/sumRootToLeafNumber.cpp), [Python](./algorithms/python/SumRootToLeafNumbers/sumNumbers.py)|Medium|
|128|[Longest Consecutive Sequence](https://leetcode.com/problems/longest-consecutive-sequence/)| [C++](./algorithms/cpp/longestConsecutiveSequence/longestConsecutiveSequence.cpp)|Hard|
|127|[Word Ladder](https://leetcode.com/problems/word-ladder/)| [C++](./algorithms/cpp/wordLadder/wordLadder.cpp)|Medium|
|126|[Word Ladder II](https://leetcode.com/problems/word-ladder-ii/)| [C++](./algorithms/cpp/wordLadder/wordLadder.II.cpp)|Hard|
|125|[Valid Palindrome](https://leetcode.com/problems/valid-palindrome/)| [C++](./algorithms/cpp/validPalindrome/validPalindrome.cpp), [Java](./algorithms/java/src/validPalindrome/ValidPalindrome.java)|Easy|
|124|[Binary Tree Maximum Path Sum](https://leetcode.com/problems/binary-tree-maximum-path-sum/)| [C++](./algorithms/cpp/binaryTreeMaximumPathSum/binaryTreeMaximumPathSum.cpp), [Java](./algorithms/java/src/binaryTreeMaximumPathSum/binaryTreeMaximumPathSum.java)|Hard|
|123|[Best Time to Buy and Sell Stock III](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iii/)| [C++](./algorithms/cpp/bestTimeToBuyAndSellStock/bestTimeToBuyAndSellStock.III.cpp)|Hard|
|122|[Best Time to Buy and Sell Stock II](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/)| [C++](./algorithms/cpp/bestTimeToBuyAndSellStock/bestTimeToBuyAndSellStock.II.cpp)|Medium|
|121|[Best Time to Buy and Sell Stock](https://leetcode.com/problems/best-time-to-buy-and-sell-stock/)| [C++](./algorithms/cpp/bestTimeToBuyAndSellStock/bestTimeToBuyAndSellStock.cpp)|Medium|
|120|[Triangle](https://leetcode.com/problems/triangle/)| [C++](./algorithms/cpp/triangle/triangle.cpp), [Java](./algorithms/java/src/dynamicProgramming/triangle/triangle.java)|Medium|
|119|[Pascal's Triangle II](https://leetcode.com/problems/pascals-triangle-ii/)| [C++](./algorithms/cpp/pascalTriangle/pascalTriangle.II.cpp)|Easy|
|118|[Pascal's Triangle](https://leetcode.com/problems/pascals-triangle/)| [C++](./algorithms/cpp/pascalTriangle/pascalTriangle.cpp)|Easy|
|117|[Populating Next Right Pointers in Each Node II](https://leetcode.com/problems/populating-next-right-pointers-in-each-node-ii/)| [C++](./algorithms/cpp/populatingNextRightPointersInEachNode/populatingNextRightPointersInEachNode.II.cpp), [Python](./algorithms/python/PopulatingNextRightPointersInEachNodeII/connect.py)|Hard|
|116|[Populating Next Right Pointers in Each Node](https://leetcode.com/problems/populating-next-right-pointers-in-each-node/)| [C++](./algorithms/cpp/populatingNextRightPointersInEachNode/populatingNextRightPointersInEachNode.cpp), [Python](./algorithms/python/PopulatingNextRightPointersInEachNode/connect.py)|Medium|
|115|[Distinct Subsequences](https://leetcode.com/problems/distinct-subsequences/)| [C++](./algorithms/cpp/distinctSubsequences/distinctSubsequences.cpp)|Hard|
|114|[Flatten Binary Tree to Linked List](https://leetcode.com/problems/flatten-binary-tree-to-linked-list/)| [C++](./algorithms/cpp/flattenBinaryTreeToLinkedList/flattenBinaryTreeToLinkedList.cpp), [Python](./algorithms/python/FlattenBinaryTreeToLinkedList/flatten.py)|Medium|
|113|[Path Sum II](https://leetcode.com/problems/path-sum-ii/)| [C++](./algorithms/cpp/pathSum/pathSum.II.cpp), [Python](./algorithms/python/PathSumII/pathSum.py)|Medium|
|112|[Path Sum](https://leetcode.com/problems/path-sum/)| [C++](./algorithms/cpp/pathSum/pathSum.cpp)|Easy|
|111|[Minimum Depth of Binary Tree](https://leetcode.com/problems/minimum-depth-of-binary-tree/)| [C++](./algorithms/cpp/minimumDepthOfBinaryTree/minimumDepthOfBinaryTree.cpp)|Easy|
|110|[Balanced Binary Tree](https://leetcode.com/problems/balanced-binary-tree/)| [C++](./algorithms/cpp/balancedBinaryTree/balancedBinaryTree.cpp), [Java](./algorithms/java/src/balancedBinaryTree/balancedBinaryTree.java)|Easy|
|109|[Convert Sorted List to Binary Search Tree](https://leetcode.com/problems/convert-sorted-list-to-binary-search-tree/)| [C++](./algorithms/cpp/convertSortedListToBinarySearchTree/convertSortedListToBinarySearchTree.cpp)|Medium|
|108|[Convert Sorted Array to Binary Search Tree](https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/)| [C++](./algorithms/cpp/convertSortedArrayToBinarySearchTree/convertSortedArrayToBinarySearchTree.cpp)|Medium|
|107|[Binary Tree Level Order Traversal II](https://leetcode.com/problems/binary-tree-level-order-traversal-ii/)| [C++](./algorithms/cpp/binaryTreeLevelOrderTraversal/binaryTreeLevelOrderTraversal.II.cpp)|Easy|
|106|[Construct Binary Tree from Inorder and Postorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/)| [C++](./algorithms/cpp/constructBinaryTreeFromInorderAndPostorderTraversal/constructBinaryTreeFromInorderAndPostorderTraversal.cpp), [Python](./algorithms/python/ConstructBinaryTreeFromInorderAndPostorderTraversal/buildTree.py)|Medium|
|105|[Construct Binary Tree from Preorder and Inorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/)| [C++](./algorithms/cpp/constructBinaryTreeFromPreorderAndInorderTraversal/constructBinaryTreeFromPreorderAndInorderTraversal.cpp), [Python](./algorithms/python/ConstructBinaryTreeFromPreorderAndInorderTraversal/buildTree.py)|Medium|
|104|[Maximum Depth of Binary Tree](https://leetcode.com/problems/maximum-depth-of-binary-tree/)| [C++](./algorithms/cpp/maximumDepthOfBinaryTree/maximumDepthOfBinaryTree.cpp), [Java](./algorithms/java/src/maximumDepthOfBinaryTree/maximumDepthOfBinaryTree.java)|Easy|
|103|[Binary Tree Zigzag Level Order Traversal](https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/)| [C++](./algorithms/cpp/binaryTreeZigzagLevelOrderTraversal/binaryTreeZigzagLevelOrderTraversal.cpp), [Python](./algorithms/python/BinaryTreeZigzagLevelOrderTraversal/zigzagLevelOrder.py)|Medium|
|102|[Binary Tree Level Order Traversal](https://leetcode.com/problems/binary-tree-level-order-traversal/)| [C++](./algorithms/cpp/binaryTreeLevelOrderTraversal/binaryTreeLevelOrderTraversal.cpp), [Java](./algorithms/java/src/binaryTreeLevelOrderTraversal/binaryTreeLevelOrderTraversal.java)|Easy|
|101|[Symmetric Tree](https://leetcode.com/problems/symmetric-tree/)| [C++](./algorithms/cpp/symmetricTree/symmetricTree.cpp)|Easy|
|100|[Same Tree](https://leetcode.com/problems/same-tree/)| [C++](./algorithms/cpp/sameTree/sameTree.cpp)|Easy|
|99|[Recover Binary Search Tree](https://leetcode.com/problems/recover-binary-search-tree/)| [C++](./algorithms/cpp/recoverBinarySearchTree/recoverBinarySearchTree.cpp)|Hard|
|98|[Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/)| [C++](./algorithms/cpp/validateBinarySearchTree/validateBinarySearchTree.cpp), [Java](./algorithms/java/src/validateBinarySearchTree/validateBinarySearchTree.java), [Python](./algorithms/python/ValidateBinarySearchTree/isValidBST.py)|Medium|
|97|[Interleaving String](https://leetcode.com/problems/interleaving-string/)| [C++](./algorithms/cpp/interleavingString/interleavingString.cpp)|Hard|
|96|[Unique Binary Search Trees](https://leetcode.com/problems/unique-binary-search-trees/)| [C++](./algorithms/cpp/uniqueBinarySearchTrees/uniqueBinarySearchTrees.cpp), [Python](./algorithms/python/UniqueBinarySearchTrees/numTrees.py)|Medium|
|95|[Unique Binary Search Trees II](https://leetcode.com/problems/unique-binary-search-trees-ii/)| [C++](./algorithms/cpp/uniqueBinarySearchTrees/uniqueBinarySearchTrees.II.cpp), [Python](./algorithms/python/UniqueBinarySearchTreesII/generateTrees.py)|Medium|
|94|[Binary Tree Inorder Traversal](https://leetcode.com/problems/binary-tree-inorder-traversal/)| [C++](./algorithms/cpp/binaryTreeInorderTraversal/binaryTreeInorderTraversal.cpp)|Medium|
|93|[Restore IP Addresses](https://leetcode.com/problems/restore-ip-addresses/)| [C++](./algorithms/cpp/restoreIPAddresses/restoreIPAddresses.cpp)|Medium|
|92|[Reverse Linked List II](https://leetcode.com/problems/reverse-linked-list-ii/)| [C++](./algorithms/cpp/reverseLinkedList/reverseLinkedList.II.cpp), [Java](./algorithms/java/src/reverseLinkedListII/ReverseLinkedListII.java), [Python](./algorithms/python/ReverseLinkedListII/reverseBetween.py)|Medium|
|91|[Decode Ways](https://leetcode.com/problems/decode-ways/)| [C++](./algorithms/cpp/decodeWays/decodeWays.cpp)|Medium|
|90|[Subsets II](https://leetcode.com/problems/subsets-ii/)| [C++](./algorithms/cpp/subsets/subsets.II.cpp), [Java](./algorithms/java/src/subsets/subsetsII.java)|Medium|
|89|[Gray Code](https://leetcode.com/problems/gray-code/)| [C++](./algorithms/cpp/grayCode/grayCode.cpp)|Medium|
|88|[Merge Sorted Array](https://leetcode.com/problems/merge-sorted-array/)| [C++](./algorithms/cpp/mergeTwoSortedArray/mergeTwoSortedArray.cpp)|Easy|
|87|[Scramble String](https://leetcode.com/problems/scramble-string/)| [C++](./algorithms/cpp/scrambleString/scrambleString.cpp)|Hard|
|86|[Partition List](https://leetcode.com/problems/partition-list/)| [C++](./algorithms/cpp/partitionList/partitionList.cpp), [Python](./algorithms/python/PartitionList/partition.py)|Medium|
|85|[Maximal Rectangle](https://leetcode.com/problems/maximal-rectangle/)| [C++](./algorithms/cpp/maximalRectangle/maximalRectangle.cpp)|Hard|
|84|[Largest Rectangle in Histogram](https://leetcode.com/problems/largest-rectangle-in-histogram/)| [C++](./algorithms/cpp/largestRectangleInHistogram/largestRectangleInHistogram.cpp)|Hard|
|83|[Remove Duplicates from Sorted List](https://leetcode.com/problems/remove-duplicates-from-sorted-list/)| [C++](./algorithms/cpp/removeDuplicatesFromSortedList/removeDuplicatesFromSortedList.cpp)|Easy|
|82|[Remove Duplicates from Sorted List II](https://leetcode.com/problems/remove-duplicates-from-sorted-list-ii/)| [C++](./algorithms/cpp/removeDuplicatesFromSortedList/removeDuplicatesFromSortedList.II.cpp), [Python](./algorithms/python/RemoveDuplicatesFromSortedListII/deleteDuplicates.py)|Medium|
|81|[Search in Rotated Sorted Array II](https://leetcode.com/problems/search-in-rotated-sorted-array-ii/)| [C++](./algorithms/cpp/searchInRotatedSortedArray/searchInRotatedSortedArray.II.cpp)|Medium|
|80|[Remove Duplicates from Sorted Array II](https://leetcode.com/problems/remove-duplicates-from-sorted-array-ii/)| [C++](./algorithms/cpp/removeDuplicatesFromSortedArray/removeDuplicatesFromSortedArray.II.cpp)|Medium|
|79|[Word Search](https://leetcode.com/problems/word-search/)| [C++](./algorithms/cpp/wordSearch/wordSearch.cpp)|Medium|
|78|[Subsets](https://leetcode.com/problems/subsets/)| [C++](./algorithms/cpp/subsets/subsets.cpp), [Java](./algorithms/java/src/subsets/subsets.java), [Python](./algorithms/python/Subsets/subsets.py)|Medium|
|77|[Combinations](https://leetcode.com/problems/combinations/)| [C++](./algorithms/cpp/combinations/combinations.cpp)|Medium|
|76|[Minimum Window Substring](https://leetcode.com/problems/minimum-window-substring/)| [C++](./algorithms/cpp/minimumWindowSubstring/minimumWindowSubstring.cpp)|Hard|
|75|[Sort Colors](https://leetcode.com/problems/sort-colors/)| [C++](./algorithms/cpp/sortColors/sortColors.cpp)|Medium|
|74|[Search a 2D Matrix](https://leetcode.com/problems/search-a-2d-matrix/)| [C++](./algorithms/cpp/search2DMatrix/search2DMatrix.cpp), [Java](./algorithms/java/src/search2DMatrix/search2DMatrix.java)|Medium|
|73|[Set Matrix Zeroes](https://leetcode.com/problems/set-matrix-zeroes/)| [C++](./algorithms/cpp/setMatrixZeroes/setMatrixZeroes.cpp)|Medium|
|72|[Edit Distance](https://leetcode.com/problems/edit-distance/)| [C++](./algorithms/cpp/editDistance/editDistance.cpp)|Hard|
|71|[Simplify Path](https://leetcode.com/problems/simplify-path/)| [C++](./algorithms/cpp/simplifyPath/simplifyPath.cpp)|Medium|
|70|[Climbing Stairs](https://leetcode.com/problems/climbing-stairs/)| [C++](./algorithms/cpp/climbStairs/climbStairs.cpp), [Java](./algorithms/java/src/dynamicProgramming/climbStairs/climbStairs.java)|Easy|
|69|[Sqrt(x)](https://leetcode.com/problems/sqrtx/)| [C++](./algorithms/cpp/sqrt/sqrt.cpp)|Medium|
|68|[Text Justification](https://leetcode.com/problems/text-justification/)| [C++](./algorithms/cpp/textJustification/textJustification.cpp)|Hard|
|67|[Add Binary](https://leetcode.com/problems/add-binary/)| [C++](./algorithms/cpp/addBinary/addBinary.cpp)|Easy|
|66|[Plus One](https://leetcode.com/problems/plus-one/)| [C++](./algorithms/cpp/plusOne/plusOne.cpp)|Easy|
|65|[Valid Number](https://leetcode.com/problems/valid-number/)| [C++](./algorithms/cpp/validNumber/validNumber.cpp)|Easy|
|64|[Minimum Path Sum](https://leetcode.com/problems/minimum-path-sum/)| [C++](./algorithms/cpp/minimumPathSum/minimumPathSum.cpp), [Java](./algorithms/java/src/dynamicProgramming/minimumPathSum/minimumPathSum.java)|Medium|
|63|[Unique Paths II](https://leetcode.com/problems/unique-paths-ii/)| [C++](./algorithms/cpp/uniquePaths/uniquePaths.II.cpp), [Java](./algorithms/java/src/dynamicProgramming/uniquePaths/uniquePathsII.java)|Medium|
|62|[Unique Paths](https://leetcode.com/problems/unique-paths/)| [C++](./algorithms/cpp/uniquePaths/uniquePaths.cpp), [Java](./algorithms/java/src/dynamicProgramming/uniquePaths/uniquePaths.java)|Medium|
|61|[Rotate List](https://leetcode.com/problems/rotate-list/)| [C++](./algorithms/cpp/rotateList/rotateList.cpp)|Medium|
|60|[Permutation Sequence](https://leetcode.com/problems/permutation-sequence/)| [C++](./algorithms/cpp/permutationSequence/permutationSequence.cpp)|Medium|
|59|[Spiral Matrix II](https://leetcode.com/problems/spiral-matrix-ii/)| [C++](./algorithms/cpp/spiralMatrix/spiralMatrix.II.cpp)|Medium|
|58|[Length of Last Word](https://leetcode.com/problems/length-of-last-word/)| [C++](./algorithms/cpp/lengthOfLastWord/lengthOfLastWord.cpp), [Java](./algorithms/java/src/lengthOfLastWord/LengthOfLastWord.java)|Easy|
|57|[Insert Interval](https://leetcode.com/problems/insert-interval/)| [C++](./algorithms/cpp/insertInterval/insertInterval.cpp)|Hard|
|56|[Merge Intervals](https://leetcode.com/problems/merge-intervals/)| [C++](./algorithms/cpp/mergeIntervals/mergeIntervals.cpp)|Hard|
|55|[Jump Game](https://leetcode.com/problems/jump-game/)| [C++](./algorithms/cpp/jumpGame/jumpGame.cpp), [Python](./algorithms/python/jumpGame/jumpGame.py)|Medium|
|54|[Spiral Matrix](https://leetcode.com/problems/spiral-matrix/)| [C++](./algorithms/cpp/spiralMatrix/spiralMatrix.cpp)|Medium|
|53|[Maximum Subarray](https://leetcode.com/problems/maximum-subarray/)| [C++](./algorithms/cpp/maximumSubArray/maximumSubArray.cpp), [Java](./algorithms/java/src/MaxSubArray/MaxSubarray.java)|Medium|
|52|[N-Queens II](https://leetcode.com/problems/n-queens-ii/)| [C++](./algorithms/cpp/nQueens/nQueuens.II.cpp)|Hard|
|51|[N-Queens](https://leetcode.com/problems/n-queens/)| [C++](./algorithms/cpp/nQueens/nQueuens.cpp)|Hard|
|50|["Pow(x, n)"](https://leetcode.com/problems/powx-n/)| [C++](./algorithms/cpp/pow/pow.cpp), [Java](./algorithms/java/src/powXn/PowXn.java)|Medium|
|49|[Group Anagrams](https://leetcode.com/problems/anagrams/)| [C++](./algorithms/cpp/anagrams/GroupAnagrams.cpp)|Medium|
|48|[Rotate Image](https://leetcode.com/problems/rotate-image/)| [C++](./algorithms/cpp/rotateImage/rotateImage.cpp)|Medium|
|47|[Permutations II](https://leetcode.com/problems/permutations-ii/)| [C++](./algorithms/cpp/permutations/permutations.II.cpp)|Hard|
|46|[Permutations](https://leetcode.com/problems/permutations/)| [C++](./algorithms/cpp/permutations/permutations.cpp)|Medium|
|45|[Jump Game II](https://leetcode.com/problems/jump-game-ii/)| [C++](./algorithms/cpp/jumpGame/jumpGame.II.cpp)|Hard|
|44|[Wildcard Matching](https://leetcode.com/problems/wildcard-matching/)| [C++](./algorithms/cpp/wildcardMatching/wildcardMatching.cpp)|Hard|
|43|[Multiply Strings](https://leetcode.com/problems/multiply-strings/)| [C++](./algorithms/cpp/multiplyStrings/multiplyStrings.cpp)|Medium|
|42|[Trapping Rain Water](https://leetcode.com/problems/trapping-rain-water/)| [C++](./algorithms/cpp/trappingRainWater/trappingRainWater.cpp)|Hard|
|41|[First Missing Positive](https://leetcode.com/problems/first-missing-positive/)| [C++](./algorithms/cpp/firstMissingPositive/firstMissingPositive.cpp), [Python](././algorithms/python/firstMissingPositive/firstMissingPositive.py)|Hard|
|40|[Combination Sum II](https://leetcode.com/problems/combination-sum-ii/)| [C++](./algorithms/cpp/combinationSum/combinationSum.II.cpp)|Medium|
|39|[Combination Sum](https://leetcode.com/problems/combination-sum/)| [C++](./algorithms/cpp/combinationSum/combinationSum.cpp)|Medium|
|38|[Count and Say](https://leetcode.com/problems/count-and-say/)| [C++](./algorithms/cpp/countAndSay/countAndSay.cpp), [Java](./algorithms/java/src/countAndSay/CountAndSay.java)|Easy|
|37|[Sudoku Solver](https://leetcode.com/problems/sudoku-solver/)| [C++](./algorithms/cpp/sudokuSolver/sudokuSolver.cpp)|Hard|
|36|[Valid Sudoku](https://leetcode.com/problems/valid-sudoku/)| [C++](./algorithms/cpp/validSudoku/validSudoku.cpp)|Easy|
|35|[Search Insert Position](https://leetcode.com/problems/search-insert-position/)| [C++](./algorithms/cpp/searchInsertPosition/searchInsertPosition.cpp), [Java](./algorithms/java/src/searchInsertPosition/searchInsertPosition.java)|Medium|
|34|[Search for a Range](https://leetcode.com/problems/search-for-a-range/)| [C++](./algorithms/cpp/searchForRange/searchForRange.cpp), [Java](./algorithms/java/src/searchForRange/searchForRange.java)|Medium|
|33|[Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/)| [C++](./algorithms/cpp/searchInRotatedSortedArray/searchInRotatedSortedArray.cpp), [Java](./algorithms/java/src/searchInRotatedSortedArray/searchInRotatedSortedArray.java)|Hard|
|32|[Longest Valid Parentheses](https://leetcode.com/problems/longest-valid-parentheses/)| [C++](./algorithms/cpp/longestValidParentheses/longestValidParentheses.cpp)|Hard|
|31|[Next Permutation](https://leetcode.com/problems/next-permutation/)| [C++](./algorithms/cpp/nextPermutation/nextPermutation.cpp)|Medium|
|30|[Substring with Concatenation of All Words](https://leetcode.com/problems/substring-with-concatenation-of-all-words/)| [C++](./algorithms/cpp/substringWithConcatenationOfAllWords/substringWithConcatenationOfAllWords.cpp)|Hard|
|29|[Divide Two Integers](https://leetcode.com/problems/divide-two-integers/)| [C++](./algorithms/cpp/divideTwoInt/divideTwoInt.cpp)|Medium|
|28|[Implement strStr()](https://leetcode.com/problems/implement-strstr/)| [C++](./algorithms/cpp/strStr/strStr.cpp), [Java](./algorithms/java/src/strStr/strStr.java)|Easy|
|27|[Remove Element](https://leetcode.com/problems/remove-element/)| [C++](./algorithms/cpp/removeElement/removeElement.cpp)|Easy|
|26|[Remove Duplicates from Sorted Array](https://leetcode.com/problems/remove-duplicates-from-sorted-array/)| [C++](./algorithms/cpp/removeDuplicatesFromSortedArray/removeDuplicatesFromSortedArray.cpp), [Java](./algorithms/java/src/removeDuplicatesFromSortedArray/RemoveDuplicatesFromSortedArray.java)|Easy|
|25|[Reverse Nodes in k-Group](https://leetcode.com/problems/reverse-nodes-in-k-group/)| [C++](./algorithms/cpp/reverseNodesInKGroup/reverseNodesInKGroup.cpp)|Hard|
|24|[Swap Nodes in Pairs](https://leetcode.com/problems/swap-nodes-in-pairs/)| [C++](./algorithms/cpp/swapNodesInPairs/swapNodesInPairs.cpp)|Medium|
|23|[Merge k Sorted Lists](https://leetcode.com/problems/merge-k-sorted-lists/)| [C++](./algorithms/cpp/mergeKSortedLists/mergeKSortedLists.cpp)|Hard|
|22|[Generate Parentheses](https://leetcode.com/problems/generate-parentheses/)| [C++](./algorithms/cpp/generateParentheses/generateParentheses.cpp)|Medium|
|21|[Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists/)| [C++](./algorithms/cpp/mergeTwoSortedList/mergeTwoSortedList.cpp)|Easy|
|20|[Valid Parentheses](https://leetcode.com/problems/valid-parentheses/)| [C++](./algorithms/cpp/validParentheses/validParentheses.cpp)|Easy|
|19|[Remove Nth Node From End of List](https://leetcode.com/problems/remove-nth-node-from-end-of-list/)| [C++](./algorithms/cpp/removeNthNodeFromEndOfList/removeNthNodeFromEndOfList.cpp), [Python](./algorithms/python/RemoveNthNodeFromEndOfList/removeNthFromEnd.py)|Easy|
|18|[4Sum](https://leetcode.com/problems/4sum/)| [C++](./algorithms/cpp/4Sum/4Sum.cpp)|Medium|
|17|[Letter Combinations of a Phone Number](https://leetcode.com/problems/letter-combinations-of-a-phone-number/)| [C++](./algorithms/cpp/letterCombinationsOfAPhoneNumber/letterCombinationsOfAPhoneNumber.cpp)|Medium|
|16|[3Sum Closest](https://leetcode.com/problems/3sum-closest/)| [C++](./algorithms/cpp/3SumClosest/3SumClosest.cpp)|Medium|
|15|[3Sum](https://leetcode.com/problems/3sum/)| [C++](./algorithms/cpp/3Sum/3Sum.cpp)|Medium|
|14|[Longest Common Prefix](https://leetcode.com/problems/longest-common-prefix/)| [C++](./algorithms/cpp/longestCommonPrefix/longestCommonPrefix.cpp)|Easy|
|13|[Roman to Integer](https://leetcode.com/problems/roman-to-integer/)| [C++](./algorithms/cpp/romanToInteger/romanToInteger.cpp)|Easy|
|12|[Integer to Roman](https://leetcode.com/problems/integer-to-roman/)| [C++](./algorithms/cpp/integerToRoman/integerToRoman.cpp)|Medium|
|11|[Container With Most Water](https://leetcode.com/problems/container-with-most-water/)| [C++](./algorithms/cpp/containerWithMostWater/containerWithMostWater.cpp), [Java](./algorithms/java/src/containerwithmostwater.java)|Medium|
|10|[Regular Expression Matching](https://leetcode.com/problems/regular-expression-matching/)| [C++](./algorithms/cpp/regularExpressionMatching/regularExpressionMatching.cpp)|Hard|
|9|[Palindrome Number](https://leetcode.com/problems/palindrome-number/)| [C++](./algorithms/cpp/palindromeNumber/palindromeNumber.cpp), [Java](./algorithms/java/src/palindromeNumber/PalindromeNumber.java)|Easy|
|8|[String to Integer (atoi)](https://leetcode.com/problems/string-to-integer-atoi/)| [C++](./algorithms/cpp/stringToIntegerAtoi/stringToIntegerAtoi.cpp)|Easy|
|7|[Reverse Integer](https://leetcode.com/problems/reverse-integer/)| [C++](./algorithms/cpp/reverseInteger/reverseInteger.cpp)|Easy|
|6|[ZigZag Conversion](https://leetcode.com/problems/zigzag-conversion/)| [C++](./algorithms/cpp/zigZagConversion/zigZagConversion.cpp)|Easy|
|5|[Longest Palindromic Substring](https://leetcode.com/problems/longest-palindromic-substring/)| [C++](./algorithms/cpp/longestPalindromicSubstring/longestPalindromicSubstring.cpp)|Medium|
|4|[Median of Two Sorted Arrays](https://leetcode.com/problems/median-of-two-sorted-arrays/)| [C++](./algorithms/cpp/medianOfTwoSortedArrays/medianOfTwoSortedArrays.cpp)|Hard|
|3|[Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/)| [C++](./algorithms/cpp/longestSubstringWithoutRepeatingCharacters/longestSubstringWithoutRepeatingCharacters.cpp)|Medium|
|2|[Add Two Numbers](https://leetcode.com/problems/add-two-numbers/)| [C++](./algorithms/cpp/addTwoNumbers/addTwoNumbers.cpp)|Medium|
|1|[Two Sum](https://leetcode.com/problems/two-sum/)| [C++](./algorithms/cpp/twoSum/twoSum.cpp), [Go](./algorithms/golang/twoSum/twoSum.go)|Easy|


### LeetCode Shell


| # | Title | Solution | Difficulty |
|---| ----- | -------- | ---------- |
|4|[Tenth Line](https://leetcode.com/problems/tenth-line/)| [Bash](./shell/TenthLine.sh)|Easy|
|3|[Transpose File](https://leetcode.com/problems/transpose-file/)| [Bash](./shell/TransposeFile.sh)|Medium|
|2|[Valid Phone Numbers](https://leetcode.com/problems/valid-phone-numbers/)| [Bash](./shell/ValidPhoneNumbers.sh)|Easy|
|1|[Word Frequency](https://leetcode.com/problems/word-frequency/)| [Bash](./shell/WordFrequency.sh)|Medium|

### LintCode    

| # | Title | Solution | Difficulty |
|---| ----- | -------- | ---------- |
|1|[Search in a big sorted array](http://www.lintcode.com/en/problem/search-in-a-big-sorted-array/)|[Java](./algorithms/java/src/searchInABigSortedArray/searchInABigSortedArray.java)|Medium|
|2|[Search Range in Binary Search Tree](http://www.lintcode.com/en/problem/search-range-in-binary-search-tree/) | [Java](./algorithms/java/src/searchRangeInBinarySearchTree/searchRangeInBinarySearchTree.java)|Medium|