Runtime: 215 ms, faster than 80.55% of JavaScript online submissions …

…for Count Sub Islands.

Memory Usage: 62 MB, less than 68.52% of JavaScript online submissions for Count Sub Islands.

count-sub-islands.js

@@ -5,17 +5,17 @@
  */
  var countSubIslands = function(grid1, grid2) {
     let answer = 0; 
-
-    var notCovered = function(r, c){
+    // No hay array booleano porque los visitados se marcan en grid2 con un 2
+    var area = function(r, c){
         if(r < 0 || c < 0 || r == grid1.length || c == grid1[0].length || grid2[r][c] != 1) return 0;
 
         grid2[r][c] = 2; 
-        return (grid1[r][c] == grid2[r][c] ? 0 : 1) + notCovered(r, c-1) + notCovered(r-1, c) + notCovered(r, c+1) + notCovered(r+1, c);
+        return (grid1[r][c] === 1 ? 0 : 1) + area(r, c-1) + area(r-1, c) + area(r, c+1) + area(r+1, c);
     }
 
     for (let i = 0; i < grid1.length; i++) {
         for (let j = 0; j < grid1[0].length; j++) {
-            if(notCovered(i, j) == 0) answer++;
+            if(grid2[i][j] === 1 && area(i, j) === 0) answer++;
         }
     }    
     return answer;