problem

approach

walkthrough

solution

island count

Write a function, islandCount, that takes in a grid containing Ws and Ls. W represents water and L represents land. The function should return the number of islands on the grid. An island is a vertically or horizontally connected region of land.

const grid = [
  ['W', 'L', 'W', 'W', 'W'],
  ['W', 'L', 'W', 'W', 'W'],
  ['W', 'W', 'W', 'L', 'W'],
  ['W', 'W', 'L', 'L', 'W'],
  ['L', 'W', 'W', 'L', 'L'],
  ['L', 'L', 'W', 'W', 'W'],
];

islandCount(grid); // -> 3

const grid = [
  ['L', 'W', 'W', 'L', 'W'],
  ['L', 'W', 'W', 'L', 'L'],
  ['W', 'L', 'W', 'L', 'W'],
  ['W', 'W', 'W', 'W', 'W'],
  ['W', 'W', 'L', 'L', 'L'],
];

islandCount(grid); // -> 4

const grid = [
  ['L', 'L', 'L'],
  ['L', 'L', 'L'],
  ['L', 'L', 'L'],
];

islandCount(grid); // -> 1

 const grid = [
  ['W', 'W'],
  ['W', 'W'],
  ['W', 'W'],
];

islandCount(grid); // -> 0

editor — island-count.js

saved