Class Solution


  • public class Solution
    extends Object
    200 - Number of Islands.

    Medium

    Given an m x n 2D binary grid grid which represents a map of '1's (land) and '0's (water), return the number of islands.

    An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded by water.

    Example 1:

    Input:

     grid = [
       ["1","1","1","1","0"],
       ["1","1","0","1","0"],
       ["1","1","0","0","0"],
       ["0","0","0","0","0"]
     ]
    

    Output: 1

    Example 2:

    Input:

     grid = [
       ["1","1","0","0","0"],
       ["1","1","0","0","0"],
       ["0","0","1","0","0"],
       ["0","0","0","1","1"]
     ]
    

    Output: 3

    Constraints:

    • m == grid.length
    • n == grid[i].length
    • 1 <= m, n <= 300
    • grid[i][j] is '0' or '1'.
    • Constructor Detail

      • Solution

        public Solution()
    • Method Detail

      • numIslands

        public int numIslands​(char[][] grid)