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 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:
bool check(TreeNode *root, int current_sum, int target_sum)
{
    if(!root)
        return false;
    current_sum += root->val;
    
    if(!root->left && !root->right)
    {
        return (current_sum  == target_sum);
    }
    
    
    return check(root->left, current_sum, target_sum) || check(root->right, current_sum, target_sum);
                
 }

bool hasPathSum(TreeNode *root, int sum) 
{
    if(!root)
        return false;
    return check(root, 0, sum);
}

};