Merge pull request gzc426#298 from coolbhy/patch-4

gzc426 · web-flow · commit 162c980a479e · 2018-12-04T17:23:47.000+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 +1,30 @@
+```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) {
+        Queue<TreeNode> q = new LinkedList<>();
+        q.add(root);
+        q.add(root);
+        while(!q.isEmpty()){
+            TreeNode r1=q.poll();
+            TreeNode r2=q.poll();
+            if(r1==null&&r2==null)continue;
+            if(r1==null||r2==null)return false;
+            if(r1.val!=r2.val)return false;
+            q.add(r1.left);
+            q.add(r2.right);
+            q.add(r1.right);
+            q.add(r2.left);
+        }
+        return true;
+    }
+}
+```
