Time: 236 ms (81.16%), Space: 20.1 MB (68.88%) - LeetHub

Author: wlsgur11

0200-number-of-islands/0200-number-of-islands.py

@@ -0,0 +1,34 @@
+from collections import deque
+
+class Solution:
+    def numIslands(self, grid: List[List[str]]) -> int:
+        n = len(grid)
+        m = len(grid[0])
+        visited = [[False] * m for _ in range(n)]
+        cnt = 0
+        
+        def bfs(a, b):
+            q = deque([(a, b)])
+            dx = [1, -1, 0, 0]
+            dy = [0, 0, 1, -1]
+
+            while q:
+                x, y = q.popleft()
+
+                for i in range(4):
+                    nx = x + dx[i]
+                    ny = y + dy[i]
+
+                    if 0 <= nx < n and 0 <= ny < m and not visited[nx][ny] and grid[nx][ny] == '1':
+                        q.append((nx, ny))
+                        visited[nx][ny] = True
+
+
+
+        for i in range(n):
+            for j in range(m):
+                if grid[i][j] == '1' and not visited[i][j]:
+                    bfs(i, j)
+                    cnt += 1
+
+        return cnt