题解 | 迷宫寻路

dfs

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void dfs(char[][] chs,int i,int j){
        if(chs[i][j]=='#'){
            return ;
        }
        int n=chs.length;
        int m=chs[0].length;
        chs[i][j]='#';
        if(i-1>=0){
            dfs(chs,i-1,j);
        }
        if(i+1<n){
            dfs(chs,i+1,j);
        }
        if(j-1>=0){
            dfs(chs,i,j-1);

        }
        if(j+1<m){
            dfs(chs,i,j+1);

        }
    }
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n=in.nextInt();
        int m=in.nextInt();
        char[][] chs=new char[n][m];
        for(int i=0;i<n;i++){
            chs[i]=in.next().toCharArray();
        }
        if(chs[0][0]=='#'||chs[n-1][m-1]=='#'){
            System.out.println("No");
        }else{
            dfs(chs,0,0);
            if(chs[n-1][m-1]=='#'){
                System.out.println("Yes");
            }else{
                System.out.println("No");
            }

        }
    }
}