Minimum Depth of Binary Tree 二叉树的最小深度

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.

/** * Definition for binary tree * struct TreeNode { *     int val; *     TreeNode *left; *     TreeNode *right; *     TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ //注意是叶子节点，左右都为空的节点才是class Solution {public:    int minDepth(TreeNode *root) {        if(root==NULL)           return 0;        if(root->left==NULL && root->right==NULL)           return 1;        int leftDep,rightDep;                leftDep=minDepth(root->left);        rightDep=minDepth(root->right);        if(leftDep==0)            return rightDep+1;        else if(rightDep==0)            return leftDep+1;        return (leftDep<rightDep?leftDep:rightDep)+1;    }};