update project structure

leetcode_py/36.py

@@ -0,0 +1,23 @@
+# Valid Sudoku
+
+
+class Solution:
+    def isValidSudoku(self, board: list[list[int]]) -> bool:
+        rows = [set() for _ in range(9)]
+        cols = [set() for _ in range(9)]
+        boxes = [set() for _ in range(9)]
+
+        for i in range(9):
+            for j in range(9):
+                num = board[i][j]
+                if num != ".":
+                    box_index = (i // 3) * 3 + j // 3
+
+                    if num in rows[i] or num in cols[j] or num in boxes[box_index]:
+                        return False
+
+                    rows[i].add(num)
+                    cols[j].add(num)
+                    boxes[box_index].add(num)
+
+        return True