Added tasks 28-57

Author: ThanhNIT

README.md

@@ -245,6 +245,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0054 |[Spiral Matrix](src/main/python/g0001_0100/s0054_spiral_matrix/Solution.java)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Matrix, Simulation | 0 | 100.00
 
 #### Day 2 String
 
@@ -344,6 +345,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0057 |[Insert Interval](src/main/python/g0001_0100/s0057_insert_interval/Solution.java)| Medium | 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
 
 #### Day 18 Stack
@@ -430,6 +432,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
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 | 0074 |[Search a 2D Matrix](src/main/python/g0001_0100/s0074_search_a_2d_matrix/Solution0074.py)| Medium | Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) | 0 | 100.00
+| 0054 |[Spiral Matrix](src/main/python/g0001_0100/s0054_spiral_matrix/Solution.java)| 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
 | 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
@@ -530,6 +533,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0012 |[Integer to Roman](src/main/python/g0001_0100/s0012_integer_to_roman/Solution0012.py)| Medium | String, Hash_Table, Math, Big_O_Time_O(1)_Space_O(1) | 0 | 100.00
 | 0014 |[Longest Common Prefix](src/main/python/g0001_0100/s0014_longest_common_prefix/Solution0014.py)| Easy | Top_Interview_Questions, String, Big_O_Time_O(n\*m)_Space_O(m) | 0 | 100.00
 | 0006 |[Zigzag Conversion](src/main/python/g0001_0100/s0006_zigzag_conversion/Solution0006.py)| Medium | String, Big_O_Time_O(n)_Space_O(n) | 5 | 93.09
+| 0028 |[Implement strStr()](src/main/python/g0001_0100/s0028_find_the_index_of_the_first_occurrence_in_a_string/Solution.java)| Easy | Top_Interview_Questions, String, Two_Pointers, String_Matching | 0 | 100.00
 
 #### Top Interview 150 Two Pointers
 
@@ -543,12 +547,15 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
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 | 0003 |[Longest Substring Without Repeating Characters](src/main/python/g0001_0100/s0003_longest_substring_without_repeating_characters/Solution0003.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(n)_Space_O(1), AI_can_be_used_to_solve_the_task | 9 | 97.01
+| 0030 |[Substring with Concatenation of All Words](src/main/python/g0001_0100/s0030_substring_with_concatenation_of_all_words/Solution.java)| Hard | String, Hash_Table, Sliding_Window | 11 | 97.43
 | 0076 |[Minimum Window Substring](src/main/python/g0001_0100/s0076_minimum_window_substring/Solution0076.py)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, String, Hash_Table, Sliding_Window, Big_O_Time_O(s.length())_Space_O(1) | 59 | 88.78
 
 #### Top Interview 150 Matrix
 
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+| 0036 |[Valid Sudoku](src/main/python/g0001_0100/s0036_valid_sudoku/Solution.java)| Medium | Top_Interview_Questions, Array, Hash_Table, Matrix | 1 | 100.00
+| 0054 |[Spiral Matrix](src/main/python/g0001_0100/s0054_spiral_matrix/Solution.java)| 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
 
@@ -565,6 +572,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
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 | 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/Solution.java)| Medium | Array | 0 | 100.00
 
 #### Top Interview 150 Stack
 
@@ -729,6 +737,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0036 |[Valid Sudoku](src/main/python/g0001_0100/s0036_valid_sudoku/Solution.java)| Medium | Top_Interview_Questions, Array, Hash_Table, Matrix | 1 | 100.00
 | 0074 |[Search a 2D Matrix](src/main/python/g0001_0100/s0074_search_a_2d_matrix/Solution0074.py)| Medium | Top_100_Liked_Questions, Array, Binary_Search, Matrix, Big_O_Time_O(endRow+endCol)_Space_O(1) | 0 | 100.00
 
 #### Day 6 String
@@ -1495,6 +1504,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0028 |[Implement strStr()](src/main/python/g0001_0100/s0028_find_the_index_of_the_first_occurrence_in_a_string/Solution.java)| Easy | Top_Interview_Questions, String, Two_Pointers, String_Matching | 0 | 100.00
 
 #### Day 2
 
@@ -1532,6 +1542,7 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 
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+| 0054 |[Spiral Matrix](src/main/python/g0001_0100/s0054_spiral_matrix/Solution.java)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Matrix, Simulation | 0 | 100.00
 
 #### Day 9
 
@@ -1670,8 +1681,10 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0070 |[Climbing Stairs](src/main/python/g0001_0100/s0070_climbing_stairs/Solution0070.py)| Easy | Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Memoization, Algorithm_I_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_2, Level_1_Day_10_Dynamic_Programming, Udemy_Dynamic_Programming, Top_Interview_150_1D_DP, Big_O_Time_O(n)_Space_O(n) | 0 | 100.00
 | 0064 |[Minimum Path Sum](src/main/python/g0001_0100/s0064_minimum_path_sum/Solution0064.py)| Medium | Top_100_Liked_Questions, Array, Dynamic_Programming, Matrix, Dynamic_Programming_I_Day_16, Udemy_Dynamic_Programming, Top_Interview_150_Multidimensional_DP, Big_O_Time_O(m\*n)_Space_O(m\*n) | 15 | 60.38
 | 0062 |[Unique Paths](src/main/python/g0001_0100/s0062_unique_paths/Solution0062.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Dynamic_Programming, Math, Combinatorics, LeetCode_75_DP/Multidimensional, Algorithm_II_Day_13_Dynamic_Programming, Dynamic_Programming_I_Day_15, Level_1_Day_11_Dynamic_Programming, Big_O_Time_O(m\*n)_Space_O(m\*n) | 0 | 100.00
+| 0057 |[Insert Interval](src/main/python/g0001_0100/s0057_insert_interval/Solution.java)| Medium | Array, Level_2_Day_17_Interval, Top_Interview_150_Intervals | 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, Data_Structure_II_Day_2_Array, Level_2_Day_17_Interval, Udemy_2D_Arrays/Matrix, Top_Interview_150_Intervals, Big_O_Time_O(n_log_n)_Space_O(n) | 7 | 72.98
 | 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, Algorithm_II_Day_12_Dynamic_Programming, Dynamic_Programming_I_Day_4, Udemy_Arrays, Top_Interview_150_Array/String, Big_O_Time_O(n)_Space_O(1) | 12 | 85.38
+| 0054 |[Spiral Matrix](src/main/python/g0001_0100/s0054_spiral_matrix/Solution.java)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Matrix, Simulation, Programming_Skills_II_Day_8, Level_2_Day_1_Implementation/Simulation, Udemy_2D_Arrays/Matrix, Top_Interview_150_Matrix | 0 | 100.00
 | 0053 |[Maximum Subarray](src/main/python/g0001_0100/s0053_maximum_subarray/Solution0053.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Divide_and_Conquer, Data_Structure_I_Day_1_Array, Dynamic_Programming_I_Day_5, Udemy_Famous_Algorithm, Top_Interview_150_Kadane's_Algorithm, Big_O_Time_O(n)_Space_O(1) | 50 | 77.23
 | 0051 |[N-Queens](src/main/python/g0001_0100/s0051_n_queens/Solution0051.py)| Hard | Top_100_Liked_Questions, Array, Backtracking, Big_O_Time_O(N!)_Space_O(N) | 6 | 98.12
 | 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, Data_Structure_II_Day_8_String, Programming_Skills_II_Day_11, Udemy_Strings, Top_Interview_150_Hashmap, Big_O_Time_O(n\*k_log_k)_Space_O(n) | 11 | 82.75
@@ -1681,11 +1694,14 @@ Python-based LeetCode algorithm problem solutions, regularly updated.
 | 0042 |[Trapping Rain Water](src/main/python/g0001_0100/s0042_trapping_rain_water/Solution0042.py)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Array, Dynamic_Programming, Two_Pointers, Stack, Monotonic_Stack, Dynamic_Programming_I_Day_9, Udemy_Two_Pointers, Top_Interview_150_Array/String, Big_O_Time_O(n)_Space_O(1) | 11 | 71.16
 | 0041 |[First Missing Positive](src/main/python/g0001_0100/s0041_first_missing_positive/Solution0041.py)| Hard | Top_100_Liked_Questions, Top_Interview_Questions, Array, Hash_Table, Udemy_Arrays, Big_O_Time_O(n)_Space_O(n) | 19 | 93.81
 | 0039 |[Combination Sum](src/main/python/g0001_0100/s0039_combination_sum/Solution0039.py)| Medium | Top_100_Liked_Questions, Array, Backtracking, Algorithm_II_Day_10_Recursion_Backtracking, Level_2_Day_20_Brute_Force/Backtracking, Udemy_Backtracking/Recursion, Top_Interview_150_Backtracking, Big_O_Time_O(2^n)_Space_O(n+2^n) | 4 | 90.51
+| 0036 |[Valid Sudoku](src/main/python/g0001_0100/s0036_valid_sudoku/Solution.java)| Medium | Top_Interview_Questions, Array, Hash_Table, Matrix, Data_Structure_I_Day_5_Array, Top_Interview_150_Matrix | 1 | 100.00
 | 0035 |[Search Insert Position](src/main/python/g0001_0100/s0035_search_insert_position/Solution0035.py)| Easy | Top_100_Liked_Questions, Array, Binary_Search, Algorithm_I_Day_1_Binary_Search, Binary_Search_I_Day_2, Top_Interview_150_Binary_Search, Big_O_Time_O(log_n)_Space_O(1) | 0 | 100.00
 | 0034 |[Find First and Last Position of Element in Sorted Array](src/main/python/g0001_0100/s0034_find_first_and_last_position_of_element_in_sorted_array/Solution0034.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_5, Top_Interview_150_Binary_Search, Big_O_Time_O(log_n)_Space_O(1) | 0 | 100.00
 | 0033 |[Search in Rotated Sorted Array](src/main/python/g0001_0100/s0033_search_in_rotated_sorted_array/Solution0033.py)| Medium | Top_100_Liked_Questions, Top_Interview_Questions, Array, Binary_Search, Algorithm_II_Day_1_Binary_Search, Binary_Search_I_Day_11, Level_2_Day_8_Binary_Search, Udemy_Binary_Search, Top_Interview_150_Binary_Search, Big_O_Time_O(log_n)_Space_O(1) | 0 | 100.00
 | 0032 |[Longest Valid Parentheses](src/main/python/g0001_0100/s0032_longest_valid_parentheses/Solution0032.py)| Hard | Top_100_Liked_Questions, String, Dynamic_Programming, Stack, Big_O_Time_O(n)_Space_O(1) | 6 | 66.50
 | 0031 |[Next Permutation](src/main/python/g0001_0100/s0031_next_permutation/Solution0031.py)| Medium | Top_100_Liked_Questions, Array, Two_Pointers, Big_O_Time_O(n)_Space_O(1) | 0 | 100.00
+| 0030 |[Substring with Concatenation of All Words](src/main/python/g0001_0100/s0030_substring_with_concatenation_of_all_words/Solution.java)| Hard | String, Hash_Table, Sliding_Window, Top_Interview_150_Sliding_Window | 11 | 97.43
+| 0028 |[Implement strStr()](src/main/python/g0001_0100/s0028_find_the_index_of_the_first_occurrence_in_a_string/Solution.java)| Easy | Top_Interview_Questions, String, Two_Pointers, String_Matching, Programming_Skills_II_Day_1, Top_Interview_150_Array/String | 0 | 100.00
 | 0027 |[Remove Element](src/main/python/g0001_0100/s0027_remove_element/Solution0027.py)| Easy | Array, Two_Pointers, Top_Interview_150_Array/String | 0 | 100.00
 | 0026 |[Remove Duplicates from Sorted Array](src/main/python/g0001_0100/s0026_remove_duplicates_from_sorted_array/Solution0026.py)| Easy | Top_Interview_Questions, Array, Two_Pointers, Udemy_Two_Pointers, Top_Interview_150_Array/String | 0 | 100.00
 | 0025 |[Reverse Nodes in k-Group](src/main/python/g0001_0100/s0025_reverse_nodes_in_k_group/Solution0025.py)| Hard | Top_100_Liked_Questions, Linked_List, Recursion, Data_Structure_II_Day_13_Linked_List, Udemy_Linked_List, Top_Interview_150_Linked_List, Big_O_Time_O(n)_Space_O(k) | 0 | 100.00

src/main/python/g0001_0100/s0028_find_the_index_of_the_first_occurrence_in_a_string/Solution0028.py

@@ -0,0 +1,14 @@
+# #Easy #Top_Interview_Questions #String #Two_Pointers #String_Matching
+# #Programming_Skills_II_Day_1 #Top_Interview_150_Array/String
+# #2025_09_13_Time_0_ms_(100.00%)_Space_12.36_MB_(81.86%)
+
+class Solution:
+    def strStr(self, haystack: str, needle: str) -> int:
+        if not needle:
+            return 0
+        m = len(haystack)
+        n = len(needle)
+        for start in range(m - n + 1):
+            if haystack[start:start + n] == needle:
+                return start
+        return -1

src/main/python/g0001_0100/s0028_find_the_index_of_the_first_occurrence_in_a_string/Solution0028_test.py

@@ -0,0 +1,12 @@
+import unittest
+from Solution0028 import Solution
+
+class SolutionTest(unittest.TestCase):
+    def test_strStr(self):
+        self.assertEqual(Solution().strStr("hello", "ll"), 2)
+
+    def test_strStr2(self):
+        self.assertEqual(Solution().strStr("hello", ""), 0)
+
+    def test_strStr3(self):
+        self.assertEqual(Solution().strStr("hello", "oo"), -1)

src/main/python/g0001_0100/s0028_find_the_index_of_the_first_occurrence_in_a_string/readme.md

@@ -0,0 +1,36 @@
+28\. Implement strStr()
+
+Easy
+
+Implement [strStr()](http://www.cplusplus.com/reference/cstring/strstr/).
+
+Return the index of the first occurrence of needle in haystack, or `-1` if `needle` is not part of `haystack`.
+
+**Clarification:**
+
+What should we return when `needle` is an empty string? This is a great question to ask during an interview.
+
+For the purpose of this problem, we will return 0 when `needle` is an empty string. This is consistent to C's [strstr()](http://www.cplusplus.com/reference/cstring/strstr/) and Java's [indexOf()](https://docs.oracle.com/javase/7/docs/api/java/lang/String.html#indexOf(java.lang.String)).
+
+**Example 1:**
+
+**Input:** haystack = "hello", needle = "ll"
+
+**Output:** 2 
+
+**Example 2:**
+
+**Input:** haystack = "aaaaa", needle = "bba"
+
+**Output:** -1 
+
+**Example 3:**
+
+**Input:** haystack = "", needle = ""
+
+**Output:** 0 
+
+**Constraints:**
+
+*   <code>0 <= haystack.length, needle.length <= 5 * 10<sup>4</sup></code>
+*   `haystack` and `needle` consist of only lower-case English characters.

src/main/python/g0001_0100/s0030_substring_with_concatenation_of_all_words/Solution0030.py

@@ -0,0 +1,38 @@
+# #Hard #String #Hash_Table #Sliding_Window #Top_Interview_150_Sliding_Window
+# #2025_09_13_Time_20_ms_(96.85%)_Space_13.11_MB_(74.97%)
+
+from typing import List
+
+class Solution:
+    def findSubstring(self, s: str, words: List[str]) -> List[int]:
+        ans = []
+        n1 = len(words[0])
+        n2 = len(s)
+        map1 = {}
+        for word in words:
+            map1[word] = map1.get(word, 0) + 1
+        
+        for i in range(n1):
+            left = i
+            j = i
+            c = 0
+            map2 = {}
+            while j + n1 <= n2:
+                word1 = s[j:j + n1]
+                j += n1
+                if word1 in map1:
+                    map2[word1] = map2.get(word1, 0) + 1
+                    c += 1
+                    while map2[word1] > map1[word1]:
+                        word2 = s[left:left + n1]
+                        map2[word2] = map2.get(word2, 0) - 1
+                        left += n1
+                        c -= 1
+                    if c == len(words):
+                        ans.append(left)
+                else:
+                    map2.clear()
+                    c = 0
+                    left = j
+        
+        return ans

src/main/python/g0001_0100/s0030_substring_with_concatenation_of_all_words/Solution0030_test.py

@@ -0,0 +1,25 @@
+import unittest
+from Solution0030 import Solution
+
+class SolutionTest(unittest.TestCase):
+    def test_findSubstring(self):
+        self.assertEqual(
+            Solution().findSubstring("barfoothefoobarman", ["foo", "bar"]),
+            [0, 9]
+        )
+
+    def test_findSubstring2(self):
+        self.assertEqual(
+            Solution().findSubstring(
+                "wordgoodgoodgoodbestword", ["word", "good", "best", "word"]
+            ),
+            []
+        )
+
+    def test_findSubstring3(self):
+        self.assertEqual(
+            Solution().findSubstring(
+                "barfoofoobarthefoobarman", ["bar", "foo", "the"]
+            ),
+            [6, 9, 12]
+        )

src/main/python/g0001_0100/s0030_substring_with_concatenation_of_all_words/readme.md

@@ -0,0 +1,35 @@
+30\. Substring with Concatenation of All Words
+
+Hard
+
+You are given a string `s` and an array of strings `words` of **the same length**. Return all starting indices of substring(s) in `s` that is a concatenation of each word in `words` **exactly once**, **in any order**, and **without any intervening characters**.
+
+You can return the answer in **any order**.
+
+**Example 1:**
+
+**Input:** s = "barfoothefoobarman", words = ["foo","bar"]
+
+**Output:** [0,9]
+
+**Explanation:** Substrings starting at index 0 and 9 are "barfoo" and "foobar" respectively. The output order does not matter, returning [9,0] is fine too. 
+
+**Example 2:**
+
+**Input:** s = "wordgoodgoodgoodbestword", words = ["word","good","best","word"]
+
+**Output:** [] 
+
+**Example 3:**
+
+**Input:** s = "barfoofoobarthefoobarman", words = ["bar","foo","the"]
+
+**Output:** [6,9,12] 
+
+**Constraints:**
+
+*   <code>1 <= s.length <= 10<sup>4</sup></code>
+*   `s` consists of lower-case English letters.
+*   `1 <= words.length <= 5000`
+*   `1 <= words[i].length <= 30`
+*   `words[i]` consists of lower-case English letters.

src/main/python/g0001_0100/s0036_valid_sudoku/Solution0036.py

@@ -0,0 +1,36 @@
+# #Medium #Top_Interview_Questions #Array #Hash_Table #Matrix #Data_Structure_I_Day_5_Array
+# #Top_Interview_150_Matrix #2025_09_13_Time_5_ms_(72.85%)_Space_12.40_MB_(54.10%)
+
+from typing import List
+
+class Solution:
+    def __init__(self):
+        self.j1 = 0
+        self.i1 = [0] * 9
+        self.b1 = [0] * 9
+
+    def isValidSudoku(self, board: List[List[str]]) -> bool:
+        for i in range(9):
+            for j in range(9):
+                res = self._checkValid(board, i, j)
+                if not res:
+                    return False
+        return True
+
+    def _checkValid(self, board: List[List[str]], i: int, j: int) -> bool:
+        if j == 0:
+            self.j1 = 0
+        if board[i][j] == '.':
+            return True
+        val = int(board[i][j])
+        if self.j1 == (self.j1 | (1 << (val - 1))):
+            return False
+        self.j1 |= 1 << (val - 1)
+        if self.i1[j] == (self.i1[j] | (1 << (val - 1))):
+            return False
+        self.i1[j] |= 1 << (val - 1)
+        b = (i // 3) * 3 + j // 3
+        if self.b1[b] == (self.b1[b] | (1 << (val - 1))):
+            return False
+        self.b1[b] |= 1 << (val - 1)
+        return True