112. Path Sum - LeetCode Solution

# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution:
    def hasPathSum(self, root: TreeNode, targetSum: int) -> bool:
        if not root:
            return False
        
        def trav(root, val):
            if not root.right:
                if not root.left:
                    return val + root.val == targetSum
            
            a = False
            b = False
            if root.right:
                a = trav(root.right , val + root.val)
            if root.left:
                b = trav(root.left, val + root.val)
            if a:
                return True
            if b:
                return True
            return False
    
        return trav(root, 0)