```
/**
* 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) return false;
if((root -> val == sum) && ((!root -> left) && (!root -> right))) return true;
return hasPathSum(root -> left, sum - root -> val) || hasPathSum(root -> right, sum - root -> val);
}
};
```