Added tasks 103-117

Author: ThanhNIT

README.md

@@ -295,6 +295,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0108 |[Convert Sorted Array to Binary Search Tree](src/main/python/g0101_0200/s0108_convert_sorted_array_to_binary_search_tree/Solution0108.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Tree, Binary_Tree, Binary_Search_Tree, Divide_and_Conquer | 0 | 100.00
 | 0230 |[Kth Smallest Element in a BST](src/main/python/g0201_0300/s0230_kth_smallest_element_in_a_bst/Solution0230.py)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
 
 #### Day 10 Graph/BFS/DFS
@@ -464,6 +465,8 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 |-|-|-|-|-|-
 | 0094 |[Binary Tree Inorder Traversal](src/main/python/g0001_0100/s0094_binary_tree_inorder_traversal/Solution0094.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
 | 0102 |[Binary Tree Level Order Traversal](src/main/python/g0101_0200/s0102_binary_tree_level_order_traversal/Solution0102.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) | 0 | 100.00
+| 0103 |[Binary Tree Zigzag Level Order Traversal](src/main/python/g0101_0200/s0103_binary_tree_zigzag_level_order_traversal/Solution0103.py)| Medium | Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree | 0 | 100.00
+| 0108 |[Convert Sorted Array to Binary Search Tree](src/main/python/g0101_0200/s0108_convert_sorted_array_to_binary_search_tree/Solution0108.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Tree, Binary_Tree, Binary_Search_Tree, Divide_and_Conquer | 0 | 100.00
 | 0543 |[Diameter of Binary Tree](src/main/python/g0501_0600/s0543_diameter_of_binary_tree/Solution0543.py)| Easy | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) | 3 | 94.30
 | 0100 |[Same Tree](src/main/python/g0001_0100/s0100_same_tree/Solution0100.py)| Easy | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree | 0 | 100.00
 | 0226 |[Invert Binary Tree](src/main/python/g0201_0300/s0226_invert_binary_tree/Solution0226.py)| Easy | Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
@@ -617,7 +620,10 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0226 |[Invert Binary Tree](src/main/python/g0201_0300/s0226_invert_binary_tree/Solution0226.py)| Easy | Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
 | 0101 |[Symmetric Tree](src/main/python/g0101_0200/s0101_symmetric_tree/Solution0101.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(log(N)) | 0 | 100.00
 | 0105 |[Construct Binary Tree from Preorder and Inorder Traversal](src/main/python/g0101_0200/s0105_construct_binary_tree_from_preorder_and_inorder_traversal/Solution0105.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Big_O_Time_O(N)_Space_O(N) | 4 | 73.84
+| 0106 |[Construct Binary Tree from Inorder and Postorder Traversal](src/main/python/g0101_0200/s0106_construct_binary_tree_from_inorder_and_postorder_traversal/Solution0106.py)| Medium | Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer | 0 | 100.00
+| 0117 |[Populating Next Right Pointers in Each Node II](src/main/python/g0101_0200/s0117_populating_next_right_pointers_in_each_node_ii/Solution0117.py)| Medium | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Linked_List | 44 | 70.94
 | 0114 |[Flatten Binary Tree to Linked List](src/main/python/g0101_0200/s0114_flatten_binary_tree_to_linked_list/Solution0114.py)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Big_O_Time_O(N)_Space_O(N) | 0 | 100.00
+| 0112 |[Path Sum](src/main/python/g0101_0200/s0112_path_sum/Solution0112.py)| Easy | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree | 0 | 100.00
 | 0124 |[Binary Tree Maximum Path Sum](src/main/python/g0101_0200/s0124_binary_tree_maximum_path_sum/Solution0124.py)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) | 11 | 91.40
 | 0236 |[Lowest Common Ancestor of a Binary Tree](src/main/python/g0201_0300/s0236_lowest_common_ancestor_of_a_binary_tree/Solution0236.py)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, LeetCode_75_Binary_Tree/DFS, Big_O_Time_O(n)_Space_O(n) | 41 | 97.74
 
@@ -626,6 +632,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
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 | 0102 |[Binary Tree Level Order Traversal](src/main/python/g0101_0200/s0102_binary_tree_level_order_traversal/Solution0102.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) | 0 | 100.00
+| 0103 |[Binary Tree Zigzag Level Order Traversal](src/main/python/g0101_0200/s0103_binary_tree_zigzag_level_order_traversal/Solution0103.py)| Medium | Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree | 0 | 100.00
 
 #### Top Interview 150 Binary Search Tree
 
@@ -667,6 +674,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0108 |[Convert Sorted Array to Binary Search Tree](src/main/python/g0101_0200/s0108_convert_sorted_array_to_binary_search_tree/Solution0108.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Tree, Binary_Tree, Binary_Search_Tree, Divide_and_Conquer | 0 | 100.00
 | 0148 |[Sort List](src/main/python/g0101_0200/s0148_sort_list/Solution0148.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Sorting, Two_Pointers, Linked_List, Divide_and_Conquer, Merge_Sort, Big_O_Time_O(log(N))_Space_O(log(N)) | 186 | 43.67
 | 0023 |[Merge k Sorted Lists](src/main/python/g0001_0100/s0023_merge_k_sorted_lists/Solution0023.py)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Heap_Priority_Queue, Linked_List, Divide_and_Conquer, Merge_Sort, Big_O_Time_O(k\*n\*log(k))_Space_O(log(k)) | 5 | 93.52
 
@@ -805,6 +813,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
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 | 0226 |[Invert Binary Tree](src/main/python/g0201_0300/s0226_invert_binary_tree/Solution0226.py)| Easy | Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
+| 0112 |[Path Sum](src/main/python/g0101_0200/s0112_path_sum/Solution0112.py)| Easy | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree | 0 | 100.00
 
 #### Day 13 Tree
 
@@ -912,7 +921,9 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0108 |[Convert Sorted Array to Binary Search Tree](src/main/python/g0101_0200/s0108_convert_sorted_array_to_binary_search_tree/Solution0108.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Tree, Binary_Tree, Binary_Search_Tree, Divide_and_Conquer | 0 | 100.00
 | 0105 |[Construct Binary Tree from Preorder and Inorder Traversal](src/main/python/g0101_0200/s0105_construct_binary_tree_from_preorder_and_inorder_traversal/Solution0105.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Big_O_Time_O(N)_Space_O(N) | 4 | 73.84
+| 0103 |[Binary Tree Zigzag Level Order Traversal](src/main/python/g0101_0200/s0103_binary_tree_zigzag_level_order_traversal/Solution0103.py)| Medium | Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree | 0 | 100.00
 
 #### Day 16 Tree
 
@@ -1077,6 +1088,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0117 |[Populating Next Right Pointers in Each Node II](src/main/python/g0101_0200/s0117_populating_next_right_pointers_in_each_node_ii/Solution0117.py)| Medium | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Linked_List | 44 | 70.94
 
 #### Day 8 Breadth First Search Depth First Search
 
@@ -1692,9 +1704,14 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0128 |[Longest Consecutive Sequence](src/main/python/g0101_0200/s0128_longest_consecutive_sequence/Solution0128.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Union_Find, Top_Interview_150_Hashmap, Big_O_Time_O(N_log_N)_Space_O(1) | 47 | 76.47
 | 0124 |[Binary Tree Maximum Path Sum](src/main/python/g0101_0200/s0124_binary_tree_maximum_path_sum/Solution0124.py)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Udemy_Tree_Stack_Queue, Top_Interview_150_Binary_Tree_General, Big_O_Time_O(N)_Space_O(N) | 11 | 91.40
 | 0121 |[Best Time to Buy and Sell Stock](src/main/python/g0101_0200/s0121_best_time_to_buy_and_sell_stock/Solution0121.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Data_Structure_I_Day_3_Array, Dynamic_Programming_I_Day_7, Level_1_Day_5_Greedy, Udemy_Arrays, Top_Interview_150_Array/String, Big_O_Time_O(N)_Space_O(1) | 17 | 98.03
+| 0117 |[Populating Next Right Pointers in Each Node II](src/main/python/g0101_0200/s0117_populating_next_right_pointers_in_each_node_ii/Solution0117.py)| Medium | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Linked_List, Algorithm_II_Day_7_Breadth_First_Search_Depth_First_Search, Top_Interview_150_Binary_Tree_General | 44 | 70.94
 | 0114 |[Flatten Binary Tree to Linked List](src/main/python/g0101_0200/s0114_flatten_binary_tree_to_linked_list/Solution0114.py)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Udemy_Linked_List, Top_Interview_150_Binary_Tree_General, Big_O_Time_O(N)_Space_O(N) | 0 | 100.00
+| 0112 |[Path Sum](src/main/python/g0101_0200/s0112_path_sum/Solution0112.py)| Easy | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_12_Tree, Top_Interview_150_Binary_Tree_General | 0 | 100.00
+| 0108 |[Convert Sorted Array to Binary Search Tree](src/main/python/g0101_0200/s0108_convert_sorted_array_to_binary_search_tree/Solution0108.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Tree, Binary_Tree, Binary_Search_Tree, Divide_and_Conquer, Data_Structure_II_Day_15_Tree, Level_2_Day_9_Binary_Search_Tree, Udemy_Tree_Stack_Queue, Top_Interview_150_Divide_and_Conquer | 0 | 100.00
+| 0106 |[Construct Binary Tree from Inorder and Postorder Traversal](src/main/python/g0101_0200/s0106_construct_binary_tree_from_inorder_and_postorder_traversal/Solution0106.py)| Medium | Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Top_Interview_150_Binary_Tree_General | 0 | 100.00
 | 0105 |[Construct Binary Tree from Preorder and Inorder Traversal](src/main/python/g0101_0200/s0105_construct_binary_tree_from_preorder_and_inorder_traversal/Solution0105.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Data_Structure_II_Day_15_Tree, Top_Interview_150_Binary_Tree_General, Big_O_Time_O(N)_Space_O(N) | 4 | 73.84
 | 0104 |[Maximum Depth of Binary Tree](src/main/python/g0101_0200/s0104_maximum_depth_of_binary_tree/Solution0104.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, LeetCode_75_Binary_Tree/DFS, Data_Structure_I_Day_11_Tree, Programming_Skills_I_Day_10_Linked_List_and_Tree, Udemy_Tree_Stack_Queue, Top_Interview_150_Binary_Tree_General, Big_O_Time_O(N)_Space_O(H) | 0 | 100.00
+| 0103 |[Binary Tree Zigzag Level Order Traversal](src/main/python/g0101_0200/s0103_binary_tree_zigzag_level_order_traversal/Solution0103.py)| Medium | Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_II_Day_15_Tree, Udemy_Tree_Stack_Queue, Top_Interview_150_Binary_Tree_BFS | 0 | 100.00
 | 0102 |[Binary Tree Level Order Traversal](src/main/python/g0101_0200/s0102_binary_tree_level_order_traversal/Solution0102.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Level_1_Day_6_Tree, Udemy_Tree_Stack_Queue, Top_Interview_150_Binary_Tree_BFS, Big_O_Time_O(N)_Space_O(N) | 0 | 100.00
 | 0101 |[Symmetric Tree](src/main/python/g0101_0200/s0101_symmetric_tree/Solution0101.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Level_2_Day_15_Tree, Top_Interview_150_Binary_Tree_General, Big_O_Time_O(N)_Space_O(log(N)) | 0 | 100.00
 | 0100 |[Same Tree](src/main/python/g0001_0100/s0100_same_tree/Solution0100.py)| Easy | Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Level_2_Day_15_Tree, Udemy_Tree_Stack_Queue, Top_Interview_150_Binary_Tree_General | 0 | 100.00

src/main/python/g0101_0200/s0103_binary_tree_zigzag_level_order_traversal/Solution0103.py

@@ -0,0 +1,41 @@
+# #Medium #Top_Interview_Questions #Breadth_First_Search #Tree #Binary_Tree
+# #Data_Structure_II_Day_15_Tree #Udemy_Tree_Stack_Queue #Top_Interview_150_Binary_Tree_BFS
+# #2025_09_14_Time_0_ms_(100.00%)_Space_18.25_MB_(8.14%)
+
+from typing import List, Optional
+from collections import deque
+
+class TreeNode:
+    def __init__(self, val=0, left=None, right=None):
+        self.val = val
+        self.left = left
+        self.right = right
+
+class Solution:
+    def zigzagLevelOrder(self, root: Optional[TreeNode]) -> List[List[int]]:
+        result = []
+        if root is None:
+            return result
+        q = deque()
+        q.append(root)
+        q.append(None)
+        zig = True
+        level = deque()
+        while q:
+            node = q.popleft()
+            while q and node is not None:
+                if zig:
+                    level.append(node.val)
+                else:
+                    level.appendleft(node.val)
+                if node.left is not None:
+                    q.append(node.left)
+                if node.right is not None:
+                    q.append(node.right)
+                node = q.popleft()
+            result.append(list(level))
+            zig = not zig
+            level = deque()
+            if q:
+                q.append(None)
+        return result

src/main/python/g0101_0200/s0103_binary_tree_zigzag_level_order_traversal/Solution0103_test.py

@@ -0,0 +1,24 @@
+import unittest
+from Solution0103 import Solution, TreeNode
+
+class SolutionTest(unittest.TestCase):
+    def test_zigzagLevelOrder(self):
+        root = TreeNode(3)
+        root.left = TreeNode(9)
+        root.right = TreeNode(20)
+        root.right.left = TreeNode(15)
+        root.right.right = TreeNode(7)
+        actual = Solution().zigzagLevelOrder(root)
+        expected = [[3], [20, 9], [15, 7]]
+        self.assertEqual(actual, expected)
+
+    def test_zigzagLevelOrder2(self):
+        root = TreeNode(1)
+        actual = Solution().zigzagLevelOrder(root)
+        expected = [[1]]
+        self.assertEqual(actual, expected)
+
+    def test_zigzagLevelOrder3(self):
+        actual = Solution().zigzagLevelOrder(None)
+        expected = []
+        self.assertEqual(actual, expected)

src/main/python/g0101_0200/s0103_binary_tree_zigzag_level_order_traversal/readme.md

@@ -0,0 +1,30 @@
+103\. Binary Tree Zigzag Level Order Traversal
+
+Medium
+
+Given the `root` of a binary tree, return _the zigzag level order traversal of its nodes' values_. (i.e., from left to right, then right to left for the next level and alternate between).
+
+**Example 1:**
+
+![](https://assets.leetcode.com/uploads/2021/02/19/tree1.jpg)
+
+**Input:** root = [3,9,20,null,null,15,7]
+
+**Output:** [[3],[20,9],[15,7]] 
+
+**Example 2:**
+
+**Input:** root = [1]
+
+**Output:** [[1]] 
+
+**Example 3:**
+
+**Input:** root = []
+
+**Output:** [] 
+
+**Constraints:**
+
+*   The number of nodes in the tree is in the range `[0, 2000]`.
+*   `-100 <= Node.val <= 100`

src/main/python/g0101_0200/s0106_construct_binary_tree_from_inorder_and_postorder_traversal/Solution0106.py

@@ -0,0 +1,26 @@
+# #Medium #Array #Hash_Table #Tree #Binary_Tree #Divide_and_Conquer
+# #Top_Interview_150_Binary_Tree_General #2025_09_14_Time_0_ms_(100.00%)_Space_19.02_MB_(96.74%)
+
+from typing import List, Optional
+
+class TreeNode:
+    def __init__(self, val=0, left=None, right=None):
+        self.val = val
+        self.left = left
+        self.right = right
+
+class Solution:
+    def buildTree(self, inorder: List[int], postorder: List[int]) -> Optional[TreeNode]:
+        in_index = [len(inorder) - 1]
+        post_index = [len(postorder) - 1]
+        return self._helper(inorder, postorder, in_index, post_index, float('inf'))
+
+    def _helper(self, inorder: List[int], postorder: List[int], index: List[int], p_index: List[int], target: int) -> Optional[TreeNode]:
+        if index[0] < 0 or (index[0] < len(inorder) and inorder[index[0]] == target):
+            return None
+        root = TreeNode(postorder[p_index[0]])
+        p_index[0] -= 1
+        root.right = self._helper(inorder, postorder, index, p_index, root.val)
+        index[0] -= 1
+        root.left = self._helper(inorder, postorder, index, p_index, target)
+        return root

src/main/python/g0101_0200/s0106_construct_binary_tree_from_inorder_and_postorder_traversal/Solution0106_test.py

@@ -0,0 +1,32 @@
+import unittest
+from Solution0106 import Solution
+
+class SolutionTest(unittest.TestCase):
+    def test_buildTree(self):
+        inorder = [9, 3, 15, 20, 7]
+        postorder = [9, 15, 7, 20, 3]
+        actual = Solution().buildTree(inorder, postorder)
+        # Convert tree to string representation for comparison
+        result = self._tree_to_string(actual)
+        self.assertEqual(result, "9,3,15,20,7")
+
+    def test_buildTree2(self):
+        inorder = [-1]
+        postorder = [-1]
+        actual = Solution().buildTree(inorder, postorder)
+        result = self._tree_to_string(actual)
+        self.assertEqual(result, "-1")
+
+    def _tree_to_string(self, root):
+        if root is None:
+            return ""
+        result = []
+        self._inorder_traversal(root, result)
+        return ",".join(map(str, result))
+
+    def _inorder_traversal(self, node, result):
+        if node is None:
+            return
+        self._inorder_traversal(node.left, result)
+        result.append(node.val)
+        self._inorder_traversal(node.right, result)

src/main/python/g0101_0200/s0106_construct_binary_tree_from_inorder_and_postorder_traversal/readme.md

@@ -0,0 +1,29 @@
+106\. Construct Binary Tree from Inorder and Postorder Traversal
+
+Medium
+
+Given two integer arrays `inorder` and `postorder` where `inorder` is the inorder traversal of a binary tree and `postorder` is the postorder traversal of the same tree, construct and return _the binary tree_.
+
+**Example 1:**
+
+![](https://assets.leetcode.com/uploads/2021/02/19/tree.jpg)
+
+**Input:** inorder = [9,3,15,20,7], postorder = [9,15,7,20,3]
+
+**Output:** [3,9,20,null,null,15,7] 
+
+**Example 2:**
+
+**Input:** inorder = [-1], postorder = [-1]
+
+**Output:** [-1] 
+
+**Constraints:**
+
+*   `1 <= inorder.length <= 3000`
+*   `postorder.length == inorder.length`
+*   `-3000 <= inorder[i], postorder[i] <= 3000`
+*   `inorder` and `postorder` consist of **unique** values.
+*   Each value of `postorder` also appears in `inorder`.
+*   `inorder` is **guaranteed** to be the inorder traversal of the tree.
+*   `postorder` is **guaranteed** to be the postorder traversal of the tree.