Create Path Sum - Leetcode 112.py

Author: gahogg

Path Sum - Leetcode 112.py

@@ -0,0 +1,24 @@
+# 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: Optional[TreeNode], targetSum: int) -> bool:
+
+        def has_sum(root, cur_sum):
+            if not root:
+                return False
+
+            cur_sum += root.val
+
+            if not root.left and not root.right:
+                return cur_sum == targetSum
+            
+            return has_sum(root.left, cur_sum) or \
+                   has_sum(root.right, cur_sum)
+        
+        return has_sum(root, 0)
+        # Time: O(n)
+        # Space: O(h) or O(n)