Minimum Depth Of Binary Tree Problem
Description
LeetCode Problem 111.
Given a binary tree, find its minimum depth.
The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node.
Note: A leaf is a node with no children.
Example 1:
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Input: root = [3,9,20,null,null,15,7]
Output: 2
Example 2:
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Input: root = [2,null,3,null,4,null,5,null,6]
Output: 5
Constraints:
- The number of nodes in the tree is in the range [0, 10^5].
- -1000 <= Node.val <= 1000
Sample C++ Code
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class Solution {
public:
int minDepth(TreeNode* root) {
if (root == NULL)
return 0;
if ((root->left == NULL) && (root->right == NULL))
return 1;
else if (root->left == NULL)
return minDepth(root->right) + 1;
else if (root->right == NULL)
return minDepth(root->left) + 1;
else
return min(minDepth(root->left), minDepth(root->right)) + 1;
}
};