feat(work): add Number of Islands solution

work/1/Medium/Array/200.number-of-islands.py

@@ -0,0 +1,52 @@
+"""
+200. Number of Islands
+Difficulty: Medium
+https://leetcode.com/problems/number-of-islands/
+
+──────────────────────────────────────────────────
+
+Given an m x n 2D binary grid grid which represents a map of '1's
+(land) and '0's (water), return the number of islands.
+
+An island is surrounded by water and is formed by connecting adjacent
+lands horizontally or vertically. You may assume all four edges of the
+grid are all surrounded by water.
+
+ 
+
+Example 1:
+
+Input: grid = [
+  ["1","1","1","1","0"],
+  ["1","1","0","1","0"],
+  ["1","1","0","0","0"],
+  ["0","0","0","0","0"]
+]
+Output: 1
+
+Example 2:
+
+Input: grid = [
+  ["1","1","0","0","0"],
+  ["1","1","0","0","0"],
+  ["0","0","1","0","0"],
+  ["0","0","0","1","1"]
+]
+Output: 3
+
+ 
+
+Constraints:
+
+	• m == grid.length
+
+	• n == grid[i].length
+
+	• 1 <= m, n <= 300
+
+	• grid[i][j] is '0' or '1'.
+"""
+
+class Solution:
+    def numIslands(self, grid: List[List[str]]) -> int:
+