Minimum Depth of Binary Tree

Maximum Depth of Binary Tree

可以这样写

int maxDepth(TreeNode *root) {
        if(!root)
            return 0;
        else
            return 1+max(maxDepth(root->left),maxDepth(root->right));
    }

Minimum Depth of Binary Tree

如果仿照上面

int minDepth(TreeNode *root) {
        if(!root)
            return 0;
        else
            return 1+min(minDepth(root->left),minDepth(root->right));
    }

Status: Wrong Answer

Input:	{1,2}
Output:	1
Expected:	2

根据这个错误的提示，需要加上两个判断

if(!(root->right)&&root->left)
            return 1+minDepth(root->left);
        else if(!(root->left)&&root->right)
            return 1+minDepth(root->right);

AC 完整代码：

/**
 * Definition for binary tree
 * 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->right)&&root->left)
            return 1+minDepth(root->left);
        else if(!(root->left)&&root->right)
            return 1+minDepth(root->right);
        else
            return 1+min(minDepth(root->left),minDepth(root->right));
    }
};