Added tasks 222-289

Author: ThanhNIT

README.md

@@ -393,6 +393,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0020 |[Valid Parentheses](src/main/python/g0001_0100/s0020_valid_parentheses/Solution0020.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, String, Stack, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
 | 0005 |[Longest Palindromic Substring](src/main/python/g0001_0100/s0005_longest_palindromic_substring/Solution0005.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Dynamic_Programming, Big_O_Time_O(n)_Space_O(n) | 47 | 97.38
 | 0394 |[Decode String](src/main/python/g0301_0400/s0394_decode_string/Solution0394.py)| Medium | Top_100_Liked_Questions, String, Stack, Recursion, LeetCode_75_Stack, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
+| 0242 |[Valid Anagram](src/main/python/g0201_0300/s0242_valid_anagram/Solution0242.py)| Easy | String, Hash_Table, Sorting | 11 | 72.46
 | 0049 |[Group Anagrams](src/main/python/g0001_0100/s0049_group_anagrams/Solution0049.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n\*k_log_k)_Space_O(n) | 11 | 82.75
 | 0151 |[Reverse Words in a String](src/main/python/g0101_0200/s0151_reverse_words_in_a_string/Solution0151.py)| Medium | String, Two_Pointers, LeetCode_75_Array/String | 0 | 100.00
 
@@ -553,6 +554,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0122 |[Best Time to Buy and Sell Stock II](src/main/python/g0101_0200/s0122_best_time_to_buy_and_sell_stock_ii/Solution0122.py)| Medium | Top_Interview_Questions, Array, Dynamic_Programming, Greedy | 0 | 100.00
 | 0055 |[Jump Game](src/main/python/g0001_0100/s0055_jump_game/Solution0055.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) | 12 | 85.38
 | 0045 |[Jump Game II](src/main/python/g0001_0100/s0045_jump_game_ii/Solution0045.py)| Medium | Top_100_Liked_Questions, Array, Dynamic_Programming, Greedy, Big_O_Time_O(n)_Space_O(1) | 8 | 57.34
+| 0274 |[H-Index](src/main/python/g0201_0300/s0274_h_index/Solution0274.py)| Medium | Array, Sorting, Counting_Sort | 0 | 100.00
 | 0238 |[Product of Array Except Self](src/main/python/g0201_0300/s0238_product_of_array_except_self/Solution0238.py)| Medium | Top_100_Liked_Questions, Array, Prefix_Sum, LeetCode_75_Array/String, Big_O_Time_O(n^2)_Space_O(n) | 15 | 97.12
 | 0134 |[Gas Station](src/main/python/g0101_0200/s0134_gas_station/Solution0134.py)| Medium | Top_Interview_Questions, Array, Greedy | 15 | 88.80
 | 0135 |[Candy](src/main/python/g0101_0200/s0135_candy/Solution0135.py)| Hard | Array, Greedy | 7 | 97.91
@@ -592,12 +594,14 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0054 |[Spiral Matrix](src/main/python/g0001_0100/s0054_spiral_matrix/Solution0054.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Matrix, Simulation | 0 | 100.00
 | 0048 |[Rotate Image](src/main/python/g0001_0100/s0048_rotate_image/Solution0048.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Math, Matrix, Big_O_Time_O(n^2)_Space_O(1) | 0 | 100.00
 | 0073 |[Set Matrix Zeroes](src/main/python/g0001_0100/s0073_set_matrix_zeroes/Solution0073.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Matrix, Big_O_Time_O(m\*n)_Space_O(1) | 3 | 71.07
+| 0289 |[Game of Life](src/main/python/g0201_0300/s0289_game_of_life/Solution0289.py)| Medium | Array, Matrix, Simulation | 0 | 100.00
 
 #### Top Interview 150 Hashmap
 
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 | 0205 |[Isomorphic Strings](src/main/python/g0201_0300/s0205_isomorphic_strings/Solution0205.py)| Easy | String, Hash_Table | 3 | 95.32
+| 0242 |[Valid Anagram](src/main/python/g0201_0300/s0242_valid_anagram/Solution0242.py)| Easy | String, Hash_Table, Sorting | 11 | 72.46
 | 0049 |[Group Anagrams](src/main/python/g0001_0100/s0049_group_anagrams/Solution0049.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, String, Hash_Table, Sorting, Big_O_Time_O(n\*k_log_k)_Space_O(n) | 11 | 82.75
 | 0001 |[Two Sum](src/main/python/g0001_0100/s0001_two_sum/Solution0001.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Big_O_Time_O(n)_Space_O(n), AI_can_be_used_to_solve_the_task | 0 | 100.00
 | 0202 |[Happy Number](src/main/python/g0201_0300/s0202_happy_number/Solution0202.py)| Easy | Top_Interview_Questions, Hash_Table, Math, Two_Pointers | 0 | 100.00
@@ -608,6 +612,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0228 |[Summary Ranges](src/main/python/g0201_0300/s0228_summary_ranges/Solution0228.py)| Easy | Array | 0 | 100.00
 | 0056 |[Merge Intervals](src/main/python/g0001_0100/s0056_merge_intervals/Solution0056.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Big_O_Time_O(n_log_n)_Space_O(n) | 7 | 72.98
 | 0057 |[Insert Interval](src/main/python/g0001_0100/s0057_insert_interval/Solution0057.py)| Medium | Array | 0 | 100.00
 
@@ -653,6 +658,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0129 |[Sum Root to Leaf Numbers](src/main/python/g0101_0200/s0129_sum_root_to_leaf_numbers/Solution0129.py)| Medium | Depth_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
 | 0173 |[Binary Search Tree Iterator](src/main/python/g0101_0200/s0173_binary_search_tree_iterator/Solution0173.py)| Medium | Tree, Binary_Tree, Stack, Design, Binary_Search_Tree, Iterator | 2 | 92.39
+| 0222 |[Count Complete Tree Nodes](src/main/python/g0201_0300/s0222_count_complete_tree_nodes/Solution0222.py)| Easy | Depth_First_Search, Tree, Binary_Search, Binary_Tree | 0 | 100.00
 | 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
 
 #### Top Interview 150 Binary Tree BFS
@@ -818,6 +824,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0242 |[Valid Anagram](src/main/python/g0201_0300/s0242_valid_anagram/Solution0242.py)| Easy | String, Hash_Table, Sorting | 11 | 72.46
 
 #### Day 7 Linked List
 
@@ -1352,6 +1359,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0222 |[Count Complete Tree Nodes](src/main/python/g0201_0300/s0222_count_complete_tree_nodes/Solution0222.py)| Easy | Depth_First_Search, Tree, Binary_Search, Binary_Tree | 0 | 100.00
 
 #### Day 11
 
@@ -1592,6 +1600,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0242 |[Valid Anagram](src/main/python/g0201_0300/s0242_valid_anagram/Solution0242.py)| Easy | String, Hash_Table, Sorting | 11 | 72.46
 
 #### Day 12 Class and Object
 
@@ -1735,16 +1744,21 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0322 |[Coin Change](src/main/python/g0301_0400/s0322_coin_change/Solution0322.py)| Medium | Top_100_Liked_Questions, Array, Dynamic_Programming, Breadth_First_Search, Algorithm_II_Day_18_Dynamic_Programming, Dynamic_Programming_I_Day_20, Level_2_Day_12_Dynamic_Programming, Top_Interview_150_1D_DP, Big_O_Time_O(m\*n)_Space_O(amount) | 454 | 96.33
 | 0300 |[Longest Increasing Subsequence](src/main/python/g0201_0300/s0300_longest_increasing_subsequence/Solution0300.py)| Medium | Top_100_Liked_Questions, Array, Dynamic_Programming, Binary_Search, Algorithm_II_Day_16_Dynamic_Programming, Binary_Search_II_Day_3, Dynamic_Programming_I_Day_18, Udemy_Dynamic_Programming, Top_Interview_150_1D_DP, Big_O_Time_O(n\*log_n)_Space_O(n) | 11 | 78.54
 | 0295 |[Find Median from Data Stream](src/main/python/g0201_0300/s0295_find_median_from_data_stream/MedianFinder.py)| Hard | Top_100_Liked_Questions, Sorting, Two_Pointers, Design, Heap_Priority_Queue, Data_Stream, Top_Interview_150_Heap, Big_O_Time_O(n\*log_n)_Space_O(n) | 131 | 72.46
+| 0289 |[Game of Life](src/main/python/g0201_0300/s0289_game_of_life/Solution0289.py)| Medium | Array, Matrix, Simulation, Top_Interview_150_Matrix | 0 | 100.00
 | 0287 |[Find the Duplicate Number](src/main/python/g0201_0300/s0287_find_the_duplicate_number/Solution0287.py)| Medium | Top_100_Liked_Questions, Array, Binary_Search, Two_Pointers, Bit_Manipulation, Binary_Search_II_Day_5, Big_O_Time_O(n)_Space_O(n) | 16 | 96.25
 | 0283 |[Move Zeroes](src/main/python/g0201_0300/s0283_move_zeroes/Solution0283.py)| Easy | Top_100_Liked_Questions, Array, Two_Pointers, LeetCode_75_Two_Pointers, Algorithm_I_Day_3_Two_Pointers, Programming_Skills_I_Day_6_Array, Udemy_Arrays, Big_O_Time_O(n)_Space_O(1) | 3 | 80.05
+| 0274 |[H-Index](src/main/python/g0201_0300/s0274_h_index/Solution0274.py)| Medium | Array, Sorting, Counting_Sort, Top_Interview_150_Array/String | 0 | 100.00
+| 0242 |[Valid Anagram](src/main/python/g0201_0300/s0242_valid_anagram/Solution0242.py)| Easy | String, Hash_Table, Sorting, Data_Structure_I_Day_6_String, Programming_Skills_I_Day_11_Containers_and_Libraries, Udemy_Strings, Top_Interview_150_Hashmap | 11 | 72.46
 | 0240 |[Search a 2D Matrix II](src/main/python/g0201_0300/s0240_search_a_2d_matrix_ii/Solution0240.py)| Medium | Top_100_Liked_Questions, Array, Binary_Search, Matrix, Divide_and_Conquer, Data_Structure_II_Day_4_Array, Binary_Search_II_Day_8, Big_O_Time_O(n+m)_Space_O(1) | 143 | 64.84
 | 0239 |[Sliding Window Maximum](src/main/python/g0201_0300/s0239_sliding_window_maximum/Solution0239.py)| Hard | Top_100_Liked_Questions, Array, Heap_Priority_Queue, Sliding_Window, Queue, Monotonic_Queue, Udemy_Arrays, Big_O_Time_O(n\*k)_Space_O(n+k) | 152 | 81.96
 | 0238 |[Product of Array Except Self](src/main/python/g0201_0300/s0238_product_of_array_except_self/Solution0238.py)| Medium | Top_100_Liked_Questions, Array, Prefix_Sum, LeetCode_75_Array/String, Data_Structure_II_Day_5_Array, Udemy_Arrays, Top_Interview_150_Array/String, Big_O_Time_O(n^2)_Space_O(n) | 15 | 97.12
 | 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, Data_Structure_II_Day_18_Tree, Udemy_Tree_Stack_Queue, Top_Interview_150_Binary_Tree_General, Big_O_Time_O(n)_Space_O(n) | 41 | 97.74
 | 0234 |[Palindrome Linked List](src/main/python/g0201_0300/s0234_palindrome_linked_list/Solution0234.py)| Easy | Top_100_Liked_Questions, Two_Pointers, Stack, Linked_List, Recursion, Level_2_Day_3_Linked_List, Udemy_Linked_List, Big_O_Time_O(n)_Space_O(1) | 23 | 81.92
 | 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, Data_Structure_II_Day_17_Tree, Level_2_Day_9_Binary_Search_Tree, Top_Interview_150_Binary_Search_Tree, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
+| 0228 |[Summary Ranges](src/main/python/g0201_0300/s0228_summary_ranges/Solution0228.py)| Easy | Array, Top_Interview_150_Intervals | 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, Data_Structure_I_Day_12_Tree, Level_2_Day_6_Tree, Udemy_Tree_Stack_Queue, Top_Interview_150_Binary_Tree_General, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
 | 0224 |[Basic Calculator](src/main/python/g0201_0300/s0224_basic_calculator/Solution0224.py)| Hard | String, Math, Stack, Recursion, Top_Interview_150_Stack | 19 | 93.87
+| 0222 |[Count Complete Tree Nodes](src/main/python/g0201_0300/s0222_count_complete_tree_nodes/Solution0222.py)| Easy | Depth_First_Search, Tree, Binary_Search, Binary_Tree, Binary_Search_II_Day_10, Top_Interview_150_Binary_Tree_General | 0 | 100.00
 | 0221 |[Maximal Square](src/main/python/g0201_0300/s0221_maximal_square/Solution0221.py)| Medium | Array, Dynamic_Programming, Matrix, Dynamic_Programming_I_Day_16, Top_Interview_150_Multidimensional_DP, Big_O_Time_O(m\*n)_Space_O(m\*n) | 129 | 64.49
 | 0219 |[Contains Duplicate II](src/main/python/g0201_0300/s0219_contains_duplicate_ii/Solution0219.py)| Easy | Array, Hash_Table, Sliding_Window, Top_Interview_150_Hashmap | 26 | 84.30
 | 0215 |[Kth Largest Element in an Array](src/main/python/g0201_0300/s0215_kth_largest_element_in_an_array/Solution0215.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Sorting, Heap_Priority_Queue, Divide_and_Conquer, Quickselect, LeetCode_75_Heap/Priority_Queue, Data_Structure_II_Day_20_Heap_Priority_Queue, Top_Interview_150_Heap, Big_O_Time_O(n\*log(n))_Space_O(log(n)) | 45 | 90.46

src/main/python/g0201_0300/s0222_count_complete_tree_nodes/Solution0222.py

@@ -0,0 +1,32 @@
+# #Easy #Depth_First_Search #Tree #Binary_Search #Binary_Tree #Binary_Search_II_Day_10
+# #Top_Interview_150_Binary_Tree_General #2025_09_17_Time_0_ms_(100.00%)_Space_23.29_MB_(82.07%)
+
+from typing import Optional
+
+class TreeNode:
+    def __init__(self, val: int = 0, left: Optional["TreeNode"] = None, right: Optional["TreeNode"] = None):
+        self.val = val
+        self.left = left
+        self.right = right
+
+class Solution:
+    def countNodes(self, root: Optional[TreeNode]) -> int:
+        if root is None:
+            return 0
+        left_height = self._left_height(root)
+        right_height = self._right_height(root)
+        if left_height == right_height:
+            return (1 << left_height) - 1
+        return 1 + self.countNodes(root.left) + self.countNodes(root.right)
+
+    def _left_height(self, node: Optional[TreeNode]) -> int:
+        if node is None:
+            return 0
+        return 1 + self._left_height(node.left)
+
+    def _right_height(self, node: Optional[TreeNode]) -> int:
+        if node is None:
+            return 0
+        return 1 + self._right_height(node.right)
+
+

src/main/python/g0201_0300/s0222_count_complete_tree_nodes/Solution0222_test.py

@@ -0,0 +1,18 @@
+import unittest
+from Solution0222 import Solution, TreeNode
+
+class SolutionTest(unittest.TestCase):
+    def test_countNodes(self):
+        left_left = TreeNode(4)
+        left_right = TreeNode(5)
+        left = TreeNode(2, left_left, left_right)
+        right_left = TreeNode(6)
+        right = TreeNode(3, right_left, None)
+        root = TreeNode(1, left, right)
+        self.assertEqual(Solution().countNodes(root), 6)
+
+    def test_countNodes_null(self):
+        self.assertEqual(Solution().countNodes(None), 0)
+
+    def test_countNodes_single(self):
+        self.assertEqual(Solution().countNodes(TreeNode(1)), 1)

src/main/python/g0201_0300/s0222_count_complete_tree_nodes/readme.md

@@ -0,0 +1,35 @@
+222\. Count Complete Tree Nodes
+
+Medium
+
+Given the `root` of a **complete** binary tree, return the number of the nodes in the tree.
+
+According to **[Wikipedia](http://en.wikipedia.org/wiki/Binary_tree#Types_of_binary_trees)**, every level, except possibly the last, is completely filled in a complete binary tree, and all nodes in the last level are as far left as possible. It can have between `1` and <code>2<sup>h</sup></code> nodes inclusive at the last level `h`.
+
+Design an algorithm that runs in less than `O(n)` time complexity.
+
+**Example 1:**
+
+![](https://assets.leetcode.com/uploads/2021/01/14/complete.jpg)
+
+**Input:** root = [1,2,3,4,5,6]
+
+**Output:** 6 
+
+**Example 2:**
+
+**Input:** root = []
+
+**Output:** 0 
+
+**Example 3:**
+
+**Input:** root = [1]
+
+**Output:** 1 
+
+**Constraints:**
+
+*   The number of nodes in the tree is in the range <code>[0, 5 * 10<sup>4</sup>]</code>.
+*   <code>0 <= Node.val <= 5 * 10<sup>4</sup></code>
+*   The tree is guaranteed to be **complete**.

src/main/python/g0201_0300/s0228_summary_ranges/Solution0228.py

@@ -0,0 +1,26 @@
+# #Easy #Array #Top_Interview_150_Intervals #2025_09_17_Time_0_ms_(100.00%)_Space_17.69_MB_(84.69%)
+
+from typing import List
+
+class Solution:
+    def summaryRanges(self, nums: List[int]) -> List[str]:
+        ranges: List[str] = []
+        if not nums:
+            return ranges
+        a = nums[0]
+        b = a
+        for i in range(1, len(nums)):
+            if nums[i] != b + 1:
+                if a == b:
+                    ranges.append(str(a))
+                else:
+                    ranges.append(f"{a}->{b}")
+                a = nums[i]
+                b = a
+            else:
+                b += 1
+        if a == b:
+            ranges.append(str(a))
+        else:
+            ranges.append(f"{a}->{b}")
+        return ranges

src/main/python/g0201_0300/s0228_summary_ranges/Solution0228_test.py

@@ -0,0 +1,15 @@
+import unittest
+from Solution0228 import Solution
+
+class SolutionTest(unittest.TestCase):
+    def test_summaryRanges(self):
+        self.assertEqual(
+            Solution().summaryRanges([0, 1, 2, 4, 5, 7]),
+            ["0->2", "4->5", "7"],
+        )
+
+    def test_summaryRanges2(self):
+        self.assertEqual(
+            Solution().summaryRanges([0, 2, 3, 4, 6, 8, 9]),
+            ["0", "2->4", "6", "8->9"],
+        )

src/main/python/g0201_0300/s0228_summary_ranges/readme.md

@@ -0,0 +1,53 @@
+228\. Summary Ranges
+
+Easy
+
+You are given a **sorted unique** integer array `nums`.
+
+Return _the **smallest sorted** list of ranges that **cover all the numbers in the array exactly**_. That is, each element of `nums` is covered by exactly one of the ranges, and there is no integer `x` such that `x` is in one of the ranges but not in `nums`.
+
+Each range `[a,b]` in the list should be output as:
+
+*   `"a->b"` if `a != b`
+*   `"a"` if `a == b`
+
+**Example 1:**
+
+**Input:** nums = [0,1,2,4,5,7]
+
+**Output:** ["0->2","4->5","7"]
+
+**Explanation:** The ranges are: [0,2] --> "0->2" [4,5] --> "4->5" [7,7] --> "7" 
+
+**Example 2:**
+
+**Input:** nums = [0,2,3,4,6,8,9]
+
+**Output:** ["0","2->4","6","8->9"]
+
+**Explanation:** The ranges are: [0,0] --> "0" [2,4] --> "2->4" [6,6] --> "6" [8,9] --> "8->9" 
+
+**Example 3:**
+
+**Input:** nums = []
+
+**Output:** [] 
+
+**Example 4:**
+
+**Input:** nums = [-1]
+
+**Output:** ["-1"] 
+
+**Example 5:**
+
+**Input:** nums = [0]
+
+**Output:** ["0"] 
+
+**Constraints:**
+
+*   `0 <= nums.length <= 20`
+*   <code>-2<sup>31</sup> <= nums[i] <= 2<sup>31</sup> - 1</code>
+*   All the values of `nums` are **unique**.
+*   `nums` is sorted in ascending order.

src/main/python/g0201_0300/s0242_valid_anagram/Solution0242.py

@@ -0,0 +1,17 @@
+# #Easy #String #Hash_Table #Sorting #Data_Structure_I_Day_6_String
+# #Programming_Skills_I_Day_11_Containers_and_Libraries #Udemy_Strings #Top_Interview_150_Hashmap
+# #2025_09_17_Time_11_ms_(72.46%)_Space_17.66_MB_(97.60%)
+
+class Solution:
+    def isAnagram(self, s: str, t: str) -> bool:
+        if len(s) != len(t):
+            return False
+        freq = [0] * 26
+        for ch in s:
+            freq[ord(ch) - 97] += 1
+        for ch in t:
+            idx = ord(ch) - 97
+            if freq[idx] == 0:
+                return False
+            freq[idx] -= 1
+        return True

src/main/python/g0201_0300/s0242_valid_anagram/Solution0242_test.py

@@ -0,0 +1,9 @@
+import unittest
+from Solution0242 import Solution
+
+class SolutionTest(unittest.TestCase):
+    def test_isAnagram(self):
+        self.assertTrue(Solution().isAnagram("anagram", "nagaram"))
+
+    def test_isAnagram2(self):
+        self.assertFalse(Solution().isAnagram("rat", "car"))

src/main/python/g0201_0300/s0242_valid_anagram/readme.md

@@ -0,0 +1,24 @@
+242\. Valid Anagram
+
+Easy
+
+Given two strings `s` and `t`, return `true` _if_ `t` _is an anagram of_ `s`_, and_ `false` _otherwise_.
+
+**Example 1:**
+
+**Input:** s = "anagram", t = "nagaram"
+
+**Output:** true 
+
+**Example 2:**
+
+**Input:** s = "rat", t = "car"
+
+**Output:** false 
+
+**Constraints:**
+
+*   <code>1 <= s.length, t.length <= 5 * 10<sup>4</sup></code>
+*   `s` and `t` consist of lowercase English letters.
+
+**Follow up:** What if the inputs contain Unicode characters? How would you adapt your solution to such a case?