463/kt

Author: zheeeng

463.island-perimeter.0.kt

@@ -0,0 +1,27 @@
+/*
+ * @lc app=leetcode id=463 lang=kotlin
+ *
+ * [463] Island Perimeter
+ */
+class Solution_islandPerimeter_0 {
+    fun islandPerimeter(grid: Array<IntArray>): Int {
+        val rows = grid.size
+        if (rows == 0) return 0
+        val cols = grid[0].size
+
+        return (0 until rows).fold(0) { total0, row ->
+            (0 until cols).fold(total0) { total, col ->
+            	if (grid[row][col] == 0) {
+                    total
+                } else {
+                    total + 4 -
+                        (if (grid.getOrNull(row - 1)?.getOrNull(col)?:0 == 1) 1 else 0) -
+	                    (if (grid.getOrNull(row + 1)?.getOrNull(col)?:0 == 1) 1 else 0) -
+                        (if (grid.getOrNull(row)?.getOrNull(col - 1)?:0 == 1) 1 else 0) -
+	                    (if (grid.getOrNull(row)?.getOrNull(col + 1)?:0 == 1) 1 else 0)
+
+                }
+            }
+        }
+    }
+}