BOJ - 3190 ) 뱀

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https://www.acmicpc.net/problem/3190

3190번: 뱀

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Dummy라는 게임은 뱀 이동하면서 벽이나 자기의 몸에 닿으면 끝나느 게임이다.

 

중간중간에 사과를 먹으면 몸의 길이가 늘어난다.

 

또한, 시간에 따라서 방향이 바뀌기때문에 덱을 이용하여서 사과를 먹으면 앞쪽에 좌표를 추가하고,

 

사과를 먹지않았다면, 앞쪽에 추가하고 맨뒤의 값을 poll해주면서 진행하면된다.

 

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import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayDeque;
import java.util.StringTokenizer;

public class Main {
	static class node{
		int time; char dir;
		public node(int time , char dir) {
			this.time = time ; 
			this.dir = dir;
		}
	}
	public static void main(String[] args) throws Exception{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st = new StringTokenizer(br.readLine());
		int N =Integer.parseInt(st.nextToken());
		int  map[][] = new int[N+1][N+1];
		st = new StringTokenizer(br.readLine());
		int apple = Integer.parseInt(st.nextToken());
		for(int index = 1 ; index < apple+1 ; index++) {
			st = new StringTokenizer(br.readLine());
			map[Integer.parseInt(st.nextToken())][Integer.parseInt(st.nextToken())] = 1;
		}
		st = new StringTokenizer(br.readLine());
		int move_time = Integer.parseInt(st.nextToken());
		node move_coordinate[]= new node[move_time+1];
		for(int index = 1; index < move_time+1 ; index++) {
			st = new StringTokenizer(br.readLine());
			move_coordinate[index] = new node(Integer.parseInt(st.nextToken()), st.nextToken().charAt(0));
		}
		
		ArrayDeque<int []> snake = new ArrayDeque<>();
		snake.add(new int [] {1,1});
		int dir = 3 ; // 상하좌우
		int diry[] = {-1,1,0,0};
		int dirx[] = {0,0,-1,1};
		int nowy = 0 , nowx =0;
	    int nexty = 0 , nextx = 0;
		map[1][1] = 2;
		int time = 0;
	    int index =1;
		while(true) {
	    	
	    	if(index <= move_time) {
		    	if(move_coordinate[index].time == time) {
		    		if(move_coordinate[index].dir=='D') {
		    			if(dir == 3) {dir =1;}
		    			else if(dir ==2) {dir =0;}
		    			else if(dir ==1) {dir =2;}
		    			else if(dir ==0) {dir =3;}
		    		}
		    		else if(move_coordinate[index].dir=='L') {
		    			if(dir == 3) {dir=0;}
		    			else if(dir ==2) {dir=1;}
		    			else if(dir ==1) {dir=3;}
		    			else if(dir ==0) {dir=2;}
		    		}
		    		index++;
		    	}
	    	}
	    	int now[] = snake.peek();
			nowy = now[0] ; nowx = now[1];
			
			nexty = nowy + diry[dir] ; nextx = nowx+ dirx[dir];
			if(nexty >=1 && nextx >=1 && nexty <=N && nextx <=N) {
				if(map[nexty][nextx] == 1) {
					snake.addFirst(new int[] {nexty, nextx});
					map[nexty][nextx] = 2;
				}
				else if(map[nexty][nextx] == 0) {
					int last[] =snake.pollLast();
					snake.addFirst(new int[] {nexty, nextx});
					map[last[0]][last[1]] = 0 ; map[nexty][nextx] =2;
				}
				else if(map[nexty][nextx] == 2) {
					break;
				}
			}
			else {
				break;
			}
		
			time++;
		}
		System.out.println(time+1);
	}
}

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