Added tasks 101-128

Author: ThanhNIT

README.md

@@ -104,11 +104,13 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0121 |[Best Time to Buy and Sell Stock](src/main/python/g0101_0200/s0121_best_time_to_buy_and_sell_stock/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 666 | 98.09
 
 #### Day 6 Tree
 
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+| 0102 |[Binary Tree Level Order Traversal](src/main/python/g0101_0200/s0102_binary_tree_level_order_traversal/Solution.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) | 31 | 95.63
 
 #### Day 7 Binary Search
 
@@ -249,6 +251,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0101 |[Symmetric Tree](src/main/python/g0101_0200/s0101_symmetric_tree/Solution.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)) | 35 | 71.46
 
 #### Day 16 Design
 
@@ -308,6 +311,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0121 |[Best Time to Buy and Sell Stock](src/main/python/g0101_0200/s0121_best_time_to_buy_and_sell_stock/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 666 | 98.09
 | 0283 |[Move Zeroes](src/main/python/g0201_0300/s0283_move_zeroes/Solution.py)| Easy | Top_100_Liked_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) | 113 | 97.70
 | 0001 |[Two Sum](src/main/python/g0001_0100/s0001_two_sum/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n) | 62 | 53.52
 | 0055 |[Jump Game](src/main/python/g0001_0100/s0055_jump_game/Solution.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) | 333 | 97.58
@@ -347,6 +351,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0114 |[Flatten Binary Tree to Linked List](src/main/python/g0101_0200/s0114_flatten_binary_tree_to_linked_list/Solution.py)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Big_O_Time_O(N)_Space_O(N) | 24 | 99.54
 | 0024 |[Swap Nodes in Pairs](src/main/python/g0001_0100/s0024_swap_nodes_in_pairs/Solution.py)| Medium | Top_100_Liked_Questions, Linked_List, Recursion, Big_O_Time_O(n)_Space_O(1) | 27 | 93.88
 | 0206 |[Reverse Linked List](src/main/python/g0201_0300/s0206_reverse_linked_list/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(N)_Space_O(1) | 35 | 72.56
 | 0021 |[Merge Two Sorted Lists](src/main/python/g0001_0100/s0021_merge_two_sorted_lists/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Big_O_Time_O(m+n)_Space_O(m+n) | 31 | 92.02
@@ -358,8 +363,11 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
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 | 0094 |[Binary Tree Inorder Traversal](src/main/python/g0001_0100/s0094_binary_tree_inorder_traversal/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Big_O_Time_O(n)_Space_O(n) | 28 | 91.67
+| 0102 |[Binary Tree Level Order Traversal](src/main/python/g0101_0200/s0102_binary_tree_level_order_traversal/Solution.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) | 31 | 95.63
 | 0543 |[Diameter of Binary Tree](src/main/python/g0501_0600/s0543_diameter_of_binary_tree/Solution.py)| Easy | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) | 51 | 36.84
 | 0226 |[Invert Binary Tree](src/main/python/g0201_0300/s0226_invert_binary_tree/Solution.py)| Easy | Top_100_Liked_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) | 30 | 87.85
+| 0104 |[Maximum Depth of Binary Tree](src/main/python/g0101_0200/s0104_maximum_depth_of_binary_tree/Solution.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(H) | 35 | 85.47
+| 0124 |[Binary Tree Maximum Path Sum](src/main/python/g0101_0200/s0124_binary_tree_maximum_path_sum/Solution.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) | 57 | 86.71
 | 0098 |[Validate Binary Search Tree](src/main/python/g0001_0100/s0098_validate_binary_search_tree/Solution.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Big_O_Time_O(N)_Space_O(log(N)) | 38 | 77.48
 | 0236 |[Lowest Common Ancestor of a Binary Tree](src/main/python/g0201_0300/s0236_lowest_common_ancestor_of_a_binary_tree/Solution.py)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Big_O_Time_O(n)_Space_O(n) | 43 | 89.34
 
@@ -424,6 +432,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0121 |[Best Time to Buy and Sell Stock](src/main/python/g0101_0200/s0121_best_time_to_buy_and_sell_stock/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 666 | 98.09
 
 #### Day 4 Array
 
@@ -469,6 +478,9 @@ 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/Solution.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Breadth_First_Search, Tree, Binary_Tree, Big_O_Time_O(N)_Space_O(N) | 31 | 95.63
+| 0104 |[Maximum Depth of Binary Tree](src/main/python/g0101_0200/s0104_maximum_depth_of_binary_tree/Solution.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(H) | 35 | 85.47
+| 0101 |[Symmetric Tree](src/main/python/g0101_0200/s0101_symmetric_tree/Solution.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)) | 35 | 71.46
 
 #### Day 12 Tree
 
@@ -576,6 +588,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0105 |[Construct Binary Tree from Preorder and Inorder Traversal](src/main/python/g0101_0200/s0105_construct_binary_tree_from_preorder_and_inorder_traversal/Solution.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) | 45 | 96.51
 
 #### Day 16 Tree
 
@@ -1028,6 +1041,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0121 |[Best Time to Buy and Sell Stock](src/main/python/g0101_0200/s0121_best_time_to_buy_and_sell_stock/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Big_O_Time_O(N)_Space_O(1) | 666 | 98.09
 
 #### Day 8
 
@@ -1161,6 +1175,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0104 |[Maximum Depth of Binary Tree](src/main/python/g0101_0200/s0104_maximum_depth_of_binary_tree/Solution.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(H) | 35 | 85.47
 
 #### Day 11 Containers and Libraries
 
@@ -1385,6 +1400,14 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0208 |[Implement Trie (Prefix Tree)](src/main/python/g0201_0300/s0208_implement_trie_prefix_tree/Trie.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Design, Trie, Level_2_Day_16_Design, Udemy_Trie_and_Heap, Big_O_Time_O(word.length())_or_O(prefix.length())_Space_O(N) | 140 | 28.87
 | 0207 |[Course Schedule](src/main/python/g0201_0300/s0207_course_schedule/Solution.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Graph, Topological_Sort, Big_O_Time_O(N)_Space_O(N) | 86 | 76.64
 | 0206 |[Reverse Linked List](src/main/python/g0201_0300/s0206_reverse_linked_list/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Linked_List, Recursion, Data_Structure_I_Day_8_Linked_List, Algorithm_I_Day_10_Recursion_Backtracking, Level_1_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(1) | 35 | 72.56
+| 0128 |[Longest Consecutive Sequence](src/main/python/g0101_0200/s0128_longest_consecutive_sequence/Solution.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Union_Find, Big_O_Time_O(N_log_N)_Space_O(1) | 338 | 82.56
+| 0124 |[Binary Tree Maximum Path Sum](src/main/python/g0101_0200/s0124_binary_tree_maximum_path_sum/Solution.py)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Depth_First_Search, Tree, Binary_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(N) | 57 | 86.71
+| 0121 |[Best Time to Buy and Sell Stock](src/main/python/g0101_0200/s0121_best_time_to_buy_and_sell_stock/Solution.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, Big_O_Time_O(N)_Space_O(1) | 666 | 98.09
+| 0114 |[Flatten Binary Tree to Linked List](src/main/python/g0101_0200/s0114_flatten_binary_tree_to_linked_list/Solution.py)| Medium | Top_100_Liked_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Linked_List, Udemy_Linked_List, Big_O_Time_O(N)_Space_O(N) | 24 | 99.54
+| 0105 |[Construct Binary Tree from Preorder and Inorder Traversal](src/main/python/g0101_0200/s0105_construct_binary_tree_from_preorder_and_inorder_traversal/Solution.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Tree, Binary_Tree, Divide_and_Conquer, Data_Structure_II_Day_15_Tree, Big_O_Time_O(N)_Space_O(N) | 45 | 96.51
+| 0104 |[Maximum Depth of Binary Tree](src/main/python/g0101_0200/s0104_maximum_depth_of_binary_tree/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Breadth_First_Search, Tree, Binary_Tree, Data_Structure_I_Day_11_Tree, Programming_Skills_I_Day_10_Linked_List_and_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(H) | 35 | 85.47
+| 0102 |[Binary Tree Level Order Traversal](src/main/python/g0101_0200/s0102_binary_tree_level_order_traversal/Solution.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, Big_O_Time_O(N)_Space_O(N) | 31 | 95.63
+| 0101 |[Symmetric Tree](src/main/python/g0101_0200/s0101_symmetric_tree/Solution.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, Big_O_Time_O(N)_Space_O(log(N)) | 35 | 71.46
 | 0098 |[Validate Binary Search Tree](src/main/python/g0001_0100/s0098_validate_binary_search_tree/Solution.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Binary_Search_Tree, Data_Structure_I_Day_14_Tree, Level_1_Day_8_Binary_Search_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(N)_Space_O(log(N)) | 38 | 77.48
 | 0096 |[Unique Binary Search Trees](src/main/python/g0001_0100/s0096_unique_binary_search_trees/Solution.py)| Medium | Dynamic_Programming, Math, Tree, Binary_Tree, Binary_Search_Tree, Dynamic_Programming_I_Day_11, Big_O_Time_O(n)_Space_O(1) | 30 | 84.13
 | 0094 |[Binary Tree Inorder Traversal](src/main/python/g0001_0100/s0094_binary_tree_inorder_traversal/Solution.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Depth_First_Search, Tree, Binary_Tree, Stack, Data_Structure_I_Day_10_Tree, Udemy_Tree_Stack_Queue, Big_O_Time_O(n)_Space_O(n) | 28 | 91.67

src/main/python/g0101_0200/s0101_symmetric_tree/Solution.py

@@ -0,0 +1,22 @@
+# #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
+# #Big_O_Time_O(N)_Space_O(log(N)) #2024_06_09_Time_35_ms_(71.46%)_Space_16.6_MB_(14.05%)
+
+# 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 isSymmetric(self, root: Optional[TreeNode]) -> bool:
+        if root is None:
+            return True
+        return self.helper(root.left, root.right)
+
+    def helper(self, leftNode: TreeNode, rightNode: TreeNode) -> bool:
+        if leftNode is None or rightNode is None:
+            return leftNode is None and rightNode is None
+        if leftNode.val != rightNode.val:
+            return False
+        return self.helper(leftNode.left, rightNode.right) and self.helper(leftNode.right, rightNode.left)

src/main/python/g0101_0200/s0101_symmetric_tree/readme.md

@@ -0,0 +1,63 @@
+101\. Symmetric Tree
+
+Easy
+
+Given the `root` of a binary tree, _check whether it is a mirror of itself_ (i.e., symmetric around its center).
+
+**Example 1:**
+
+![](https://assets.leetcode.com/uploads/2021/02/19/symtree1.jpg)
+
+**Input:** root = [1,2,2,3,4,4,3]
+
+**Output:** true 
+
+**Example 2:**
+
+![](https://assets.leetcode.com/uploads/2021/02/19/symtree2.jpg)
+
+**Input:** root = [1,2,2,null,3,null,3]
+
+**Output:** false 
+
+**Constraints:**
+
+*   The number of nodes in the tree is in the range `[1, 1000]`.
+*   `-100 <= Node.val <= 100`
+
+**Follow up:** Could you solve it both recursively and iteratively?
+
+To solve the "Symmetric Tree" problem in Python with the Solution class, follow these steps:
+
+1. Define a method `isSymmetric` in the `Solution` class that takes the root of a binary tree as input and returns true if the tree is symmetric, and false otherwise.
+2. Implement a recursive approach to check if the given binary tree is symmetric:
+   - Define a helper method `isMirror` that takes two tree nodes as input parameters.
+   - In the `isMirror` method, recursively compare the left and right subtrees of the given nodes.
+   - At each step, check if the values of the corresponding nodes are equal and if the left subtree of one node is a mirror image of the right subtree of the other node.
+   - If both conditions are satisfied for all corresponding nodes, return true; otherwise, return false.
+3. Call the `isMirror` method with the root's left and right children to check if the entire tree is symmetric.
+
+Here's the implementation of the `isSymmetric` method in Python:
+
+```python
+# 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 isSymmetric(self, root: TreeNode) -> bool:
+        if root is None:
+            return True
+        return self.helper(root.left, root.right)
+
+    def helper(self, leftNode: TreeNode, rightNode: TreeNode) -> bool:
+        if leftNode is None or rightNode is None:
+            return leftNode is None and rightNode is None
+        if leftNode.val != rightNode.val:
+            return False
+        return self.helper(leftNode.left, rightNode.right) and self.helper(leftNode.right, rightNode.left)
+```
+
+This implementation recursively checks whether the given binary tree is symmetric around its center in O(n) time complexity, where n is the number of nodes in the tree.

src/main/python/g0101_0200/s0102_binary_tree_level_order_traversal/Solution.py

@@ -0,0 +1,39 @@
+# #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
+# #Big_O_Time_O(N)_Space_O(N) #2024_06_09_Time_31_ms_(95.63%)_Space_17.2_MB_(85.23%)
+
+# 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
+
+from collections import deque
+
+class Solution:
+    def levelOrder(self, root: Optional[TreeNode]) -> List[List[int]]:
+        result = []
+        if not root:
+            return result
+        
+        queue = deque()
+        queue.append(root)
+        queue.append(None)
+        
+        level = []
+        while queue:
+            node = queue.popleft()
+            if node is not None:
+                level.append(node.val)
+                if node.left:
+                    queue.append(node.left)
+                if node.right:
+                    queue.append(node.right)
+            else:
+                result.append(level)
+                level = []
+                if queue:
+                    queue.append(None)
+        
+        return result