LetCode 111. 二叉树的最小深度

/**
 * 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 == NULL)
            return 0;
        if (root->left == NULL && root->right == NULL)
            return 1;
        if (root->left == NULL)
            return minDepth(root->right) + 1;
        if (root->right == NULL)
            return minDepth(root->left) + 1;
        // 改成min即可
        return min(minDepth(root->left), minDepth(root->right)) + 1;
    }
};

static int x=[](){
    std::ios::sync_with_stdio(false);
    cin.tie(NULL);
    return 0;
}();