diff --git a/solution/200/main.go b/solution/200/main.go
new file mode 100644
index 0000000..cf7b0ac
--- /dev/null
+++ b/solution/200/main.go
@@ -0,0 +1,34 @@
+package main
+
+func numIslands(grid [][]byte) int {
+    if len(grid) == 0 || len(grid[0]) == 0 {
+        return 0
+    }
+    
+    rows := len(grid)
+    cols := len(grid[0])
+    islands := 0
+    
+    var dfs func(row, col int)
+    dfs = func(row, col int) {
+        if row < 0 || col < 0 || row >= rows || col >= cols || grid[row][col] != '1' {
+            return
+        }
+        grid[row][col] = '0'
+        dfs(row-1, col)
+        dfs(row+1, col)
+        dfs(row, col-1)
+        dfs(row, col+1)
+    }
+    
+    for row := 0; row < rows; row++ {
+        for col := 0; col < cols; col++ {
+            if grid[row][col] == '1' {
+                dfs(row, col)
+                islands++
+            }
+        }
+    }
+    
+    return islands
+}