Merge pull request gzc426#274 from coolbhy/patch-3

gzc426 · web-flow · commit 547d29b0a63b · 2018-12-03T14:10:45.000+08:00
Create 啦啦啦.md
diff --git a/2018.12.4-leetcode101/啦啦啦.md b/2018.12.4-leetcode101/啦啦啦.md
@@ -0,0 +1,22 @@
+```java
+/**
+ * Definition for a binary tree node.
+ * public class TreeNode {
+ *     int val;
+ *     TreeNode left;
+ *     TreeNode right;
+ *     TreeNode(int x) { val = x; }
+ * }
+ */
+class Solution {
+    public boolean isSymmetric(TreeNode root) {
+        return cal(root,root);
+    }
+    
+    boolean cal(TreeNode r1,TreeNode r2){
+        if(r1==null&&r2==null)return true;
+        if(r1==null||r2==null)return false;
+        return r1.val==r2.val&&cal(r1.left,r2.right)&&cal(r1.right,r2.left);
+    }
+}
+```
