leetcode.com 130. Surrounded Regions

문제 링크: https://leetcode.com/problems/surrounded-regions

Author: skysign

leetcode.com 130. Surrounded Regions v2/main.py

@@ -0,0 +1,49 @@
+from typing import List
+from collections import deque
+
+
+class Solution:
+    def solve(self, board: List[List[str]]) -> None:
+        """
+        Do not return anything, modify board in-place instead.
+        """
+        r, c = len(board), len(board[0])
+        maps = [['O' for _ in range(c + 2)] for _ in range(r + 2)]
+
+        for r in range(len(board)):
+            for c in range(len(board[0])):
+                maps[r + 1][c + 1] = board[r][c]
+
+        self.bfs_Oto1(maps)
+
+        for r in range(len(maps)):
+            for c in range(len(maps[0])):
+                if maps[r][c] == 'O':
+                    maps[r][c] = 'X'
+
+        for r in range(len(maps)):
+            for c in range(len(maps[0])):
+                if maps[r][c] == '1':
+                    maps[r][c] = 'O'
+
+        for r in range(len(board)):
+            for c in range(len(board[0])):
+                board[r][c] = maps[r + 1][c + 1]
+
+    def bfs_Oto1(self, maps: List[List[str]]):
+        drc = [[-1, 0], [0, 1], [1, 0], [0, -1]]
+
+        queue = deque([[0, 0]])
+        maps[0][0] = '1'
+
+        while queue:
+            r, c = queue.popleft()
+
+            for dr, dc in drc:
+                nr, nc = r + dr, c + dc
+                if 0 <= nr < len(maps) and 0 <= nc < len(maps[0]):
+                    if maps[nr][nc] == 'O':
+                        maps[nr][nc] = '1'
+                        queue.append([nr, nc])
+
+