Symmetric Tree Problem
Description
LeetCode Problem 101.
Given the root of a binary tree, check whether it is a mirror of itself (i.e., symmetric around its center).
Example 1:
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Input: root = [1,2,2,3,4,4,3]
Output: true
Example 2:
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Input: root = [1,2,2,null,3,null,3]
Output: false
Constraints:
- The number of nodes in the tree is in the range [1, 1000].
- -100 <= Node.val <= 100
Sample C++ Code
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class Solution {
public:
bool isMirror(TreeNode* t1, TreeNode* t2) {
if ((t1 == NULL) && (t2 == NULL))
return true;
else if (t1 == NULL)
return false;
else if (t2 == NULL)
return false;
else
return (
(t1->val == t2->val) &&
isMirror(t1->left, t2->right) &&
isMirror(t1->right, t2->left)
);
}
bool isSymmetric(TreeNode* root) {
return isMirror(root, root);
}
};