Problem · Matrix

Island Perimeter (Round 3, LC 463 :)

Learn this problem
EasyMicrosoft logoMicrosoftNEW GRADONSITE INTERVIEW
See Microsoft hiring insights

Problem statement

  • Round 1: Word Pattern II 🦭
  • Round 2: Implement Queue using Stacks 🦥
  • Round 3: Island Perimeter 🦉
  • You are given row × col grid representing a map where grid[i][j] = 1 represents land and grid[i][j] = 0 represents water.

    Grid cells are connected horizontally/vertically (not diagonally). The grid is completely surrounded by water, and there is exactly one island (i.e., one or more connected land cells).

    The island doesn't have "lakes", meaning the water inside isn't connected to the water around the island. One cell is a square with side length 1. The grid is rectangular, width and height don't exceed 100. Determine the perimeter of the island.

    Function

    islandPerimeter(grid: int[][]) → int

    Complete the function islandPerimeter in the editor.

    islandPerimeter has the following parameter:

    1. int[][] grid: a 2D array of integers

    Returns

    int: the perimeter of the island

    💪 Wallz carries all! 👍

    Examples

    Example 1

    grid = [[0,1,0,0],[1,1,1,0],[0,1,0,0],[1,1,0,0]]return = 16
    The perimeter is the 16 yellow stripes in the image above.

    Example 2

    grid = [[1]]return = 4
    The perimeter is 4 since it is a single land cell with all sides surrounded by water.

    Example 3

    grid = [[1,0]]return = 4
    The perimeter is 4 since it is a single land cell with all sides surrounded by water.

    Constraints

    • row == grid.length
    • col == grid[i].length
    • 1 <= row, col <= 100
    • grid[i][j] is 0 or 1.
    • There is exactly one island in grid.

    More Microsoft problems

    drafts saved locally
    public int islandPerimeter(int[][] grid) {
      // write your code here
    }
    
    grid[[0,1,0,0],[1,1,1,0],[0,1,0,0],[1,1,0,0]]
    expected16
    checking account