/**
* 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:
void dfsWithPathSumCalc(TreeNode* root, int curSum, std::vector<int>& pathSums) {
if (!root) { return; }
curSum += root->val;
// If leaf node -> sum in pathSums
if (!root->left && !root->right) {
pathSums.push_back(curSum);
return;
}
// If not leaf node -> go to left & right sub trees
dfsWithPathSumCalc(root->left, curSum, pathSums);
dfsWithPathSumCalc(root->right, curSum, pathSums);
}
bool hasPathSum(TreeNode* root, int targetSum) {
std::vector<int> pathSums;
dfsWithPathSumCalc(root, 0, pathSums);
return (std::find(pathSums.begin(), pathSums.end(), targetSum) != pathSums.end());
}
};