[C++] 100% Runtime Iterative Solution
\nbool isSymmetric(TreeNode* root) {\n        if(!root) return true;\n        queue<TreeNode*> queue;\n        queue.push(root->left);\n        queue.push(root-
```\nbool isSymmetric(TreeNode* root) {\n        if(!root) return true;\n        queue<TreeNode*> queue;\n        queue.push(root->left);\n        queue.push(root->right);\n        while(!queue.empty()) {\n            TreeNode *left = queue.front(); queue.pop();\n            TreeNode *right = queue.front(); queue.pop();\n            if(!left && !right) continue;\n            if(!left || !right) return false;\n            if(left->val != right->val) return false;\n            queue.push(left->left);\n            queue.push(right->right);\n            queue.push(left->right);\n            queue.push(right->left);\n        }\n        return true;\n    }\n```
['C', 'Iterator', 'C++']