题解 | #二叉树的最小深度#

/**
 * struct TreeNode {
 *	int val;
 *	struct TreeNode *left;
 *	struct TreeNode *right;
 *	TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 * };
 */
class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param root TreeNode类 
     * @return int整型
     */
    int minlevel = 6000;
    void dfs(TreeNode* root,int level){
        if(root->left)
            dfs(root->left,level + 1);
        if(root->right)
            dfs(root->right,level + 1);
        if(root->left == NULL && root->right == NULL)
            minlevel = min(minlevel,level + 1);
    }
    int run(TreeNode* root) {
        // write code here
        if(root == NULL)
            return 0;
        dfs(root,0);
        return minlevel;
    }
};