[삼성기출]백준14503 - 로봇청소기

package sw;

import java.io.*;
public class Main14503_로봇청소기 {
	
	static int N,M,r,c,d,res;
	static boolean flag;
	static int[][] map;
	static int[][] dir = {{-1,0},{0,1},{1,0},{0,-1}};
	static boolean check(int x, int y) {
		if(x>=0 && x<map.length && y>=0 && y<map[x].length)
			return true;
		else return false;
	}
	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String[] input = br.readLine().trim().split(" ");
		N = Integer.parseInt(input[0]);
		M = Integer.parseInt(input[1]);
		map = new int[N][M];
		
		input = br.readLine().trim().split(" ");
		r = Integer.parseInt(input[0]);
		c = Integer.parseInt(input[1]);
		d = Integer.parseInt(input[2]);
		
		for(int i=0; i<N; i++) {
			input = br.readLine().trim().split(" ");
			for(int j=0; j<M; j++) {
				map[i][j] = Integer.parseInt(input[j]);
			}
		}
		play();
		System.out.println(res);
		
	}
	
	static int dx,dy, tmpD;
	static void play() {
		if(flag) return;
		if(map[r][c] == 0) {
			res++;
			map[r][c] = -1;
		}
		
		for(int dd=1; dd<=4; dd++) {
			tmpD = (4+d-dd)%4; // 현재방향 기준으로 좌,하,우,상 해주기 위함.
			dx = r + dir[tmpD][0];
			dy = c + dir[tmpD][1];
			if(!check(dx,dy) || map[dx][dy] == 1 || map[dx][dy] == -1) {
				continue;
			}
			else if(check(dx,dy) && map[dx][dy] == 0) {
				r = dx;
				c = dy;
				d = tmpD;
				play();
				return;
			}
		}
		
		tmpD = (d+2)%4;
		dx = r + dir[tmpD][0];
		dy = c + dir[tmpD][1];
		
		if(check(dx,dy) && map[dx][dy] != 1) {
			r = dx;
			c = dy;
			play();
		}else {
			flag = true;
		}
	}
	
	static int direct(char c) {
		if(c == 'R') {
			return (d+1)%4;
		}else {
			return (d+3)%4;
		}
	}
	static void print() {
		for(int i=0; i<N; i++) {
			for(int j=0; j<M; j++) {
				System.out.print(map[i][j]+" ");
			}
			System.out.println();
		}
	}
}