112.路径总和.cpp

/*
 * @lc app=leetcode.cn id=112 lang=cpp
 *
 * [112] 路径总和
 */

// @lc code=start
/**
 * 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:
    bool hasPathSum(TreeNode* root, int t) {
        if (!root) return false;
        t -= root->val;
        if (!root->left && !root->right) return !t;
        return hasPathSum(root->left, t) || hasPathSum(root->right, t);
    }
};
// @lc code=end