Merge pull request #1424 from ivan1016017/october14

adding algo

Author: ivanpenaloza

src/my_project/interviews/top_150_questions_round_20/path_sum.py

@@ -0,0 +1,22 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+ 
+# 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 
+        if not root.left and not root.right and root.val == targetSum: 
+            return True 
+        else: 
+            targetSum = targetSum - root.val 
+            return self.hasPathSum(root.left, targetSum) \
+                   or self.hasPathSum(root.right, targetSum)

tests/test_150_questions_round_20/test_path_sum_round_20.py

@@ -0,0 +1,17 @@
+import unittest
+from src.my_project.interviews.top_150_questions_round_20\
+.path_sum import Solution, TreeNode
+
+class HasPathSumTestCase(unittest.TestCase):
+
+    def test_is_path_sum(self):
+        solution = Solution()
+        tree = TreeNode(1, TreeNode(2), TreeNode(3))
+        output = solution.hasPathSum(root=tree, targetSum=3)
+        self.assertTrue(output)
+
+    def test_is_no_path_sum(self):
+            solution = Solution()
+            tree = TreeNode(1, TreeNode(2), TreeNode(3))
+            output = solution.hasPathSum(root=tree, targetSum=10)
+            self.assertFalse(output)