diff --git "a/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo01.java" "b/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo01.java"
new file mode 100644
index 0000000000000000000000000000000000000000..ac39b84ba9555913b74b0ce630f5bc0952bfc3d9
--- /dev/null
+++ "b/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo01.java"
@@ -0,0 +1,21 @@
+package leession;
+
+public class Demo01 {
+
+	public static void main(String[] args) {
+		System.out.println(Integer.MAX_VALUE);
+		System.out.println(Integer.MIN_VALUE);
+		System.out.println(Float.MAX_VALUE);
+		System.out.println(Float.MIN_VALUE);
+		System.out.println(Double.MIN_VALUE);
+		System.out.println(Double.MAX_VALUE);
+		System.out.println(Long.MAX_VALUE);
+		System.out.println(Long.MIN_VALUE);
+		System.out.println(Byte.MIN_VALUE);
+		System.out.println(Byte.MAX_VALUE);
+		System.out.println(Short.MIN_VALUE);
+		System.out.println(Short.MAX_VALUE);
+
+		
+	}
+}
diff --git "a/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo02.java" "b/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo02.java"
new file mode 100644
index 0000000000000000000000000000000000000000..e5eb7095ee6574427a194a71d067854c67716a1c
--- /dev/null
+++ "b/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo02.java"
@@ -0,0 +1,28 @@
+package leession;
+
+import java.util.Scanner;
+
+public class Demo02 {
+
+	public static void main(String[] args) {
+		int num01;
+		int num02;
+		int temp;
+		Scanner scanner = new Scanner(System.in);
+		System.out.println("请输入您的第一个数字");
+		num01 =scanner.nextInt();
+		System.out.println("请输入您的第二个数字");
+		num02 =scanner.nextInt();
+	
+		System.out.println("第一个数字是"+num01);
+		System.out.println("第二个数字是"+num02);
+		
+		temp = num01;
+		num01 =num02;
+		num02=temp;
+		System.out.println("互换后");
+		System.out.println("第一个数字是"+num01);
+		System.out.println("第二个数字是"+num02);
+		}
+
+}
diff --git "a/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo03.java" "b/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo03.java"
new file mode 100644
index 0000000000000000000000000000000000000000..0b1b577d0ee601f2633fe8ba06dbf12d61da4487
--- /dev/null
+++ "b/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo03.java"
@@ -0,0 +1,23 @@
+package leession;
+
+import java.util.Scanner;
+
+public class Demo03 {
+
+	public static void main(String[] args) {
+		Scanner scan = new Scanner(System.in);
+		int num01;
+		float num02;
+		double num03;
+		double sum;
+		System.out.println("输入第一个数据");
+		num01=scan.nextInt();
+		System.out.println("输入第二个数据");
+		num02=scan.nextFloat();
+		System.out.println("输入第三个数据");
+		num03=scan.nextDouble();
+		sum=num01+num02+num03;
+		System.out.println("数字总和为"+sum);
+	}
+
+}
diff --git "a/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo04.java" "b/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo04.java"
new file mode 100644
index 0000000000000000000000000000000000000000..6a3110341ce0811a0de782d7e0617d80d598ff58
--- /dev/null
+++ "b/Java\347\254\254\344\270\211\346\254\241\344\275\234\344\270\232/\346\226\271\350\215\243\346\230\237/Demo04.java"
@@ -0,0 +1,20 @@
+package leession;
+
+import java.util.Scanner;
+
+public class Demo04 {
+
+	public static void main(String[] args) {
+		float num01;
+		int num02;
+		byte num03;
+		double sum;
+		Scanner scan = new Scanner(System.in);		
+		num01= scan.nextFloat();
+		num02= scan.nextInt();
+		num03= scan.nextByte();
+		sum=num01+num02+num03;
+		System.out.println("三个数字合"+sum);
+	}
+
+}