题解 | #牛的奶量统计#

/**
 * 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 
     * @param targetSum int整型 
     * @return bool布尔型
     */
    int allSum = 0;
    bool hasPathSum(TreeNode* root, int targetSum) 
    {
        // write code here
        if (root == NULL)
        {
            return false;
        }
        targetSum -= root->val;
        if (root->left == NULL && root->right == NULL)
        {
            return targetSum == 0;
        }
        return hasPathSum(root->left, targetSum) || hasPathSum(root->right, targetSum);
    }
};