[LeetCode]Minimum Depth of Binary Tree

Minimum Depth of Binary Tree

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.

 

递归啦。

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {
public:
    int minDepth(TreeNode* root) {
        if(!root) return 0;
        if(root->left==NULL && root->right==NULL) return 1;
        int left = (root->left)?minDepth(root->left):INT_MAX;
        int right = (root->right)?minDepth(root->right):INT_MAX;
        return min(left,right)+1;
    }
};