feat: 101_symmetric_tree

101_symmetric_tree/main.cpp

@@ -0,0 +1,26 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+struct TreeNode {
+    int val;
+    TreeNode *left;
+    TreeNode *right;
+    TreeNode() : val(0), left(nullptr), right(nullptr) {}
+    TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
+    TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
+};
+
+class Solution {
+   public:
+    bool isSymmetric(TreeNode *root) {
+        if (root == nullptr) return true;
+        return isSymmetric(root->left, root->right);
+    }
+
+    bool isSymmetric(TreeNode *left, TreeNode *right) {
+        if (!left && !right) return true;
+        if (!left || !right) return false;
+        if (left->val != right->val) return false;
+        return isSymmetric(left->left, right->right) && isSymmetric(left->right, right->left);
+    }
+};