101. 对称二叉树

Author: BGMer7

src/com/gatsby/_101SymmetricTree.java

@@ -0,0 +1,26 @@
+package com.gatsby;
+
+/**
+ * @ClassName: _101SymmetricTree
+ * @Description: leetcode 101 对称二叉树
+ * @author: Gatsby
+ * @date: 2022/5/15 20:03
+ */
+
+public class _101SymmetricTree {
+    private boolean isSymmetric(TreeNode left, TreeNode right) {
+        if (left == null && right == null) return true;
+        if (left != null || right != null) return false;
+        if (left.val != right.val) return false;
+
+        return isSymmetric(left.right, right.left) && isSymmetric(right.left, left.right);
+    }
+
+    public boolean isSymmetric(TreeNode root) {
+        if (root == null) return true;
+
+        return isSymmetric(root.left, root.right);
+    }
+}
+
+