Path Sum
Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum.
For example:
Given the below binary tree and
*/For example:
Given the below binary tree and
sum = 22, 5
/ \
4 8
/ / \
11 13 4
/ \ \
7 2 1
return true, as there exist a root-to-leaf path 5->4->11->2 which sum is 22/**
* Definition for binary tree
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
class Solution {
public:
void findSum(TreeNode *node, int currSum, int const sum, bool &found){
if(node==NULL) return ;
currSum = currSum+node->val;
if(found==false&&sum==currSum&&node->left==NULL&&node->right==NULL){
found = true;
return;
}
findSum(node->left,currSum,sum,found);
findSum(node->right,currSum,sum,found);
}
bool hasPathSum(TreeNode *root, int sum) {
// Start typing your C/C++ solution below
// DO NOT write int main() function
int currSum = 0;
bool found = false;
findSum(root,currSum,sum,found);
return found;
}
};
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