[백준] BOJ - 14940 쉬운 최단거리 자바 java (실버1)

https://www.acmicpc.net/problem/14940

14940번: 쉬운 최단거리

 

 

나의풀이

import java.util.*;
import java.io.*;
public class Main {
    static int n,m;
    static int[] dx = {0,0,-1,1};
    static int[] dy = {-1,1,0,0};
    static char[][] map; 
    static boolean[][] visited;
    static int[][] answer;
    
    static public class Node{
        int x, y, move;
        
        public Node(int x, int y, int move) {
            this.x = x;
            this.y = y;
            this.move = move;
        }
    }
    
    public static void bfs(int x, int y){
        Queue<Node> q= new LinkedList<>();
        q.offer(new Node(x, y, 0));
        visited[x][y]=true;
        
        while(!q.isEmpty()){
            Node now= q.poll();
             
            // 4방향 상하좌우 
            for(int i = 0; i < 4; i++) {
                int nextX = now.x + dx[i];
                int nextY = now.y + dy[i];
                    
                // 갈수 없는 위치라면 
                if(nextX < 0 || nextY < 0 || nextX >= n || nextY >= m) {
                    continue;
                }
                
                //방문한 위치라면
                if(visited[nextX][nextY] == true) {
                    continue;
                }

                // 갈수없는 땅이면 
                if(map[nextX][nextY] == '0') {
                    answer[nextX][nextY] = 0;
                    continue;
                }
                answer[nextX][nextY]=now.move + 1;
                q.offer(new Node(nextX, nextY, now.move + 1));// 1 증가해서 큐에 넣어주기
                visited[nextX][nextY] = true;//방문처리 
            }
        }
    }
    
    public static void main(String args[]) throws Exception {
        BufferedReader br= new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw= new BufferedWriter(new OutputStreamWriter(System.out));
        StringTokenizer st= new StringTokenizer(br.readLine());
        
        n=Integer.parseInt(st.nextToken());
        m=Integer.parseInt(st.nextToken());

        map =new char[n][m];
        visited= new boolean[n][m];
        answer= new int[n][m];
        
        //지도 초기화
        for(int i=0;i<n;i++){
            st= new StringTokenizer(br.readLine());
            for(int j=0;j<m;j++){
                map[i][j]= st.nextToken().charAt(0);
            }
        }
        
        for(int i=0;i<n;i++){
            for(int j=0; j<m; j++){
                if(map[i][j] == '2'){//여기서 시작 
                    answer[i][j]=0;
                    bfs(i, j);
                }
            }
        }
        
        //결과출력
        for(int i=0;i<n;i++){
            for(int j=0; j<m; j++){
                if(answer[i][j]==0 && map[i][j] == '1'){
                    bw.write("-1 ");
                }else{
                    bw.write(answer[i][j]+" ");
                }
            }
            bw.write("\n");
        }
        
        bw.flush();
        br.close();
        bw.close();
    }
}