Create 0463-island-perimeter.js

Author: AP-Repositories

javascript/0463-island-perimeter.js

@@ -0,0 +1,23 @@
+var islandPerimeter = function(grid) {
+    const visit = new Set();
+    
+    const dfs = function(i, j) {
+        if(i >= grid.length || j >= grid[0].length || i < 0 || j < 0 || grid[i][j] == 0)
+            return 1;
+        let flatCoord = i*grid[0].length + j;
+        if(visit.has(flatCoord))
+            return 0;
+        
+        visit.add(flatCoord);
+        let perim = dfs(i, j + 1);
+        perim += dfs(i + 1, j);
+        perim += dfs(i, j - 1);
+        perim += dfs(i - 1, j);
+        return perim;
+    };
+    
+    for(let i = 0; i < grid.length; i++)
+        for(let j = 0; j < grid[0].length; j++)
+            if(grid[i][j])
+                return dfs(i, j);
+};