Nov 21

Author: siddydutta

2024-11-November-LeetCoding-Challenge/Count Unguarded Cells in the Grid.py

@@ -0,0 +1,45 @@
+from itertools import product
+from typing import List
+
+
+class Solution:
+    def countUnguarded(
+        self, m: int, n: int, guards: List[List[int]], walls: List[List[int]]
+    ) -> int:
+        grid = [[0] * n for _ in range(m)]
+        for x, y in walls:
+            grid[x][y] = 1
+        for x, y in guards:
+            grid[x][y] = 2
+
+        for x, y in guards:
+            for dx, dy in [(-1, 0), (1, 0), (0, -1), (0, 1)]:
+                nx, ny = x + dx, y + dy
+                while 0 <= nx < m and 0 <= ny < n and grid[nx][ny] <= 0:
+                    grid[nx][ny] = -1
+                    nx += dx
+                    ny += dy
+
+        unguarded = 0
+        for x, y in product(range(m), range(n)):
+            if grid[x][y] == 0:
+                unguarded += 1
+        return unguarded
+
+
+def main():
+    m = 4
+    n = 6
+    guards = [[0, 0], [1, 1], [2, 3]]
+    walls = [[0, 1], [2, 2], [1, 4]]
+    assert Solution().countUnguarded(m, n, guards, walls) == 7
+
+    m = 3
+    n = 3
+    guards = [[1, 1]]
+    walls = [[0, 1], [1, 0], [2, 1], [1, 2]]
+    assert Solution().countUnguarded(m, n, guards, walls) == 4
+
+
+if __name__ == '__main__':
+    main()

2024-11-November-LeetCoding-Challenge/README.md

@@ -23,7 +23,7 @@
 | November 18 | [1652. Defuse the Bomb](https://leetcode.com/problems/defuse-the-bomb/) | Easy | Solved |
 | November 19 | [2461. Maximum Sum of Distinct Subarrays With Length K](https://leetcode.com/problems/maximum-sum-of-distinct-subarrays-with-length-k/) | Medium | Solved |
 | November 20 | [2516. Take K of Each Character From Left and Right](https://leetcode.com/problems/take-k-of-each-character-from-left-and-right/) | Medium | Solved |
-| November 21 | []() |  |  |
+| November 21 | [2257. Count Unguarded Cells in the Grid](https://leetcode.com/problems/count-unguarded-cells-in-the-grid/) | Medium | Solved |
 | November 22 | []() |  |  |
 | November 23 | []() |  |  |
 | November 24 | []() |  |  |
@@ -38,5 +38,5 @@
 | Level  | Problems | Solved | Unsolved |
 | ---    | --- | --- | --- |
 | Easy   | 4 | 4 | 0 |
-| Medium | 15 | 8 | 7 |
+| Medium | 16 | 9 | 7 |
 | Hard   | 1 | 1 | 0 |