python: add problem 113 and unittest

Author: supercoderhawk

Python/sln_101_200/solution_111_120.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+import copy
 from typing import List
 from common_utils import *
 
@@ -23,6 +24,30 @@ def minDepth(self, root: TreeNode) -> int:
         else:
             return self.minDepth(root.right) + 1
 
+    def pathSum(self, root: TreeNode, sum: int) -> List[List[int]]:
+        """
+        113
+        :param root:
+        :param sum:
+        :return:
+        """
+        path_list = []
+
+        def check_sum(node, val, path):
+            if not node:
+                return
+            if node and node.left is None and node.right is None:
+                if val+node.val == sum:
+                    path.append(node.val)
+                    path_list.append(path)
+                return
+            path.append(node.val)
+            check_sum(node.left, val + node.val, copy.deepcopy(path))
+            check_sum(node.right, val + node.val, copy.deepcopy(path))
+
+        check_sum(root, 0, [])
+        return path_list
+
     def generate(self, numRows: int) -> List[List[int]]:
         """
         118
@@ -64,7 +89,6 @@ def getRow(self, rowIndex: int) -> List[int]:
             last_row = current_row
         return last_row
 
-
     def minimumTotal(self, triangle: List[List[int]]) -> int:
         """
         120

Python/sln_101_200/test_solution_111_120.py

@@ -1,6 +1,7 @@
 # -*- coding: utf-8 -*-
 from unittest import TestCase
 from sln_101_200.solution_111_120 import Solution_111_120
+from common_utils import build_binary_tree
 
 
 class Test_Solution_111_120(TestCase):
@@ -15,3 +16,7 @@ def test_minimumTotal(self):
             [4, 1, 8, 3]
         ]
         self.assertEqual(self.sln.minimumTotal(triangle), 11)
+
+    def test_pathSum(self):
+        tree = build_binary_tree([5, 4, 8, 11, None, 13, 4, 7, 2, None, None, 5, 1])
+        self.assertEqual(self.sln.pathSum(tree, 22), [[5, 4, 11, 2], [5, 8, 4, 5]])