题解 | 岛屿数量

import java.util.*;


public class Solution {

    private int[][] direction = new int[][] {{0, 1}, {0, -1}, {-1, 0}, {1, 0}};

       public void searchData(int x,int y,char[][] grid,int[][] bid) {
        bid[x][y] = 1;
        for (int i=0;i<4;i++) {
            int nx = x + direction[i][0];
            int ny = y + direction[i][1];
            if ( nx >= 0 && ny>=0 &&  nx < grid.length && ny < grid[0].length && grid[nx][ny] == '1' && bid[nx][ny] != 1) {
                searchData(nx,ny,grid,bid);
            }
        }
    }


    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 判断岛屿数量
     * @param grid char字符型二维数组
     * @return int整型
     */
    public int solve (char[][] grid) {
        if (grid.length == 0) {
            return 0;
        }

        int x = grid.length;
        int y = grid[0].length;
        int[][] bid = new int[x][y];
        int total = 0;
        for (int i = 0; i < x; i++) {
            for (int j = 0; j < y; j++) {
                if (bid[i][j] == 1) {
                    continue;
                }
                if (grid[i][j] == '1') {
                    total++;
                    searchData(i, j, grid, bid);
                }
            }
        }
        return total;
    }
}