Create 1254-number-of-closed-islands.ktdescription

Author: a93a

kotlin/1254-number-of-closed-islands.ktdescription

@@ -0,0 +1,41 @@
+class Solution {
+    fun closedIsland(grid: Array<IntArray>): Int {
+        val rows = grid.size
+        val cols = grid[0].size
+
+        val visited = Array(rows){BooleanArray(cols)}
+
+        fun isValid(r: Int, c: Int) = r in (0 until rows) && c in (0 until cols)
+
+        fun dfs(r: Int, c: Int): Int {
+            if(!isValid(r, c))
+                return 0
+            if(grid[r][c] == 1 || visited[r][c] == true)
+                return 1
+            
+            visited[r][c] = true
+            return minOf(
+                minOf(
+                    dfs(r + 1, c),
+                    dfs(r - 1, c)
+                ),
+                minOf(
+                    dfs(r, c + 1),
+                    dfs(r, c - 1)
+                )
+            )
+        }
+
+        var islands = 0
+        for (r in 0 until rows) {
+            for (c in 0 until cols) {
+                if (grid[r][c] == 0 && visited[r][c] == false) {
+                    if (dfs(r, c) != 0)
+                        islands++
+                }
+            }
+        }
+
+        return islands
+    }
+}