Invert Binary Tree Problem
Description
LeetCode Problem 226.
Given the root of a binary tree, invert the tree, and return its root.
Example 1:
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Input: root = [4,2,7,1,3,6,9]
Output: [4,7,2,9,6,3,1]
Example 2:
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Input: root = [2,1,3]
Output: [2,3,1]
Example 3:
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Input: root = []
Output: []
Constraints:
- The number of nodes in the tree is in the range [0, 100].
- -100 <= Node.val <= 100
Sample C++ Code
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/**
* Definition for a binary tree node.
* 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:
TreeNode* invertTree(TreeNode* root) {
if (root == NULL)
return root;
TreeNode* new_left = invertTree(root->right);
TreeNode* new_right = invertTree(root->left);
root->left = new_left;
root->right = new_right;
return root;
}
};