leetcode.com 200. Number of Islands

문제 링크: https://leetcode.com/problems/number-of-islands/description/

Author: skysign

leetcode.com 200. Number of Islands/main.py

@@ -0,0 +1,28 @@
+from typing import List
+
+
+class Solution:
+    def numIslands(self, grid: List[List[str]]) -> int:
+        MAX_ROW = len(grid)
+        MAX_COL = len(grid[0])
+        answer = 0
+
+        dyx = [[1, 0], [0, 1], [-1, 0], [0, -1]]
+
+        for row in range(MAX_ROW):
+            for col in range(MAX_COL):
+                if grid[row][col] == '1':
+                    queue = [[row, col]]
+                    grid[row][col] = 0
+                    answer += 1
+
+                    while queue:
+                        y, x = queue.pop(0)
+
+                        for dy, dx in dyx:
+                            ny, nx = y + dy, x + dx
+                            if 0 <= ny < MAX_ROW and 0 <= nx < MAX_COL and grid[ny][nx] == '1':
+                                queue.append([ny, nx])
+                                grid[ny][nx] = 0
+
+        return answer

leetcode.com 200. Number of Islands/test_main.py

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+from unittest import TestCase
+from main import Solution
+
+
+class TestSolution(TestCase):
+    def test1_num_islands(self):
+        sol = Solution()
+        self.assertEqual(1, sol.numIslands([
+  ["1","1","1","1","0"],
+  ["1","1","0","1","0"],
+  ["1","1","0","0","0"],
+  ["0","0","0","0","0"]
+]))