Initial commit

Easy/symmetric-tree/solution.cpp

@@ -0,0 +1,30 @@
+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 {
+  private:
+    bool isSymmetric(TreeNode *left, TreeNode *right) {
+        if (left == nullptr && right == nullptr) {
+            return true;
+        } else if (left == nullptr || right == nullptr) {
+            return false;
+        } else if (left->val == right->val) {
+            return isSymmetric(left->left, right->right) &&
+                   isSymmetric(left->right, right->left);
+        } else {
+            return false;
+        }
+    }
+
+  public:
+    bool isSymmetric(TreeNode *root) {
+        return isSymmetric(root->left, root->right);
+    }
+};