diff --git "a/14 \346\235\216\344\277\212\345\205\264/20221215 \344\271\235\344\271\235\344\271\230\346\263\225\350\241\250and\347\205\244\346\260\224.md" "b/14 \346\235\216\344\277\212\345\205\264/20221215 \344\271\235\344\271\235\344\271\230\346\263\225\350\241\250and\347\205\244\346\260\224.md"
new file mode 100644
index 0000000000000000000000000000000000000000..49bc3ac2eb68d396b4d0a88218932f87e93c14f7
--- /dev/null
+++ "b/14 \346\235\216\344\277\212\345\205\264/20221215 \344\271\235\344\271\235\344\271\230\346\263\225\350\241\250and\347\205\244\346\260\224.md"	
@@ -0,0 +1,42 @@
+#### 倒叙输出乘法表
+
+```java
+public class D1 {
+    public static void main(String[] args) {
+    for(int i=9;i>=1;i--){
+        for(int j=i;j>=1;j--){
+            System.out.print(j + "x" + i + "=" + i*j + "\t");
+        }
+        System.out.println();
+    }
+}
+}
+
+```
+
+### 煤气
+
+```java
+public class D2 {
+    public static void main(String[] args) {
+
+//        设二档为x，三档为（100-x）
+//        方程为x*4.05+（100-x）*5.06=445.40
+
+        for(int x=1;x<=100;x++){
+            if(x*4.05+(100-x)*5.06==445.40){
+                System.out.println("二档为" + x + "三档为" + (100-x));
+                break;
+            }
+        }
+    }
+}
+```
+
+
+
+```java
+\t 制表符;
+\n 换位符
+```
+