From c4d98c4064958a2221da8f2d3e35e82d66ee2e42 Mon Sep 17 00:00:00 2001
From: jaygala <jaygala260@gmail.com>
Date: Wed, 5 Oct 2022 14:29:07 +0530
Subject: [PATCH] added code for number of islands

---
 LeetCode/Practice/number-of-islands.py | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 LeetCode/Practice/number-of-islands.py

diff --git a/LeetCode/Practice/number-of-islands.py b/LeetCode/Practice/number-of-islands.py
new file mode 100644
index 00000000..a411efda
--- /dev/null
+++ b/LeetCode/Practice/number-of-islands.py
@@ -0,0 +1,23 @@
+class Solution:
+    def numIslands(self, grid: list[list[str]]) -> int:
+        def dfs(row, col, grid):
+            
+            if row < 0 or col < 0 or row >= len(grid) or \
+            col >= len(grid[0]) or grid[row][col] != '1':
+                return
+            
+            #mark as visited
+            grid[row][col] = 'visited'
+            
+            for dx, dy in [(-1,0),(1,0),(0,1),(0,-1)]:
+                dfs(row + dx, col + dy, grid)
+                
+        ans = 0
+
+        for row in range(len(grid)):
+            for col in range(len(grid[0])):
+                if grid[row][col] == '1':
+                    dfs(row, col, grid)
+                    ans += 1
+        return ans
+            
\ No newline at end of file