程式語言 - LeetCode - C++ - 111. Minimum Depth of Binary Tree



題目:


解答:

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:
    int minDepth(TreeNode* root) {
        if (!root) {
            return 0;
        }

        if (!root->left) {
            return minDepth(root->right) + 1;
        }
        if (!root->right) {
            return minDepth(root->left) + 1;
        }

        return min(minDepth(root->left), minDepth(root->right)) + 1;
    }
};