力扣112 路徑總和

/**
 * 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:
    bool hasPathSum(TreeNode* root, int sum) {
        if(root==nullptr) return false;
        if(root->left==nullptr&&root->right==nullptr)
        {
            return sum-root->val==0;
        }
        return hasPathSum(root->left,sum-root->val)||hasPathSum(root->right,sum-root->val);

    }
};