BOJ - 5427 ) 불

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https://www.acmicpc.net/problem/5427

불러오는 중입니다...

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불의 번짐을 Queue에 넣고 맵을 업데이트하여

그 상황에서 상근이가 갈수있는 자리를 체크해준다.

 

상근이가 가장자리에 도착할 경우 

Queue와 상관없이 종료한다.

 

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#include <iostream>
#include <queue>
#define end '\n'
using namespace std;
int N, w, h;
int dx[] = { 0,0,+1,-1 };
int dy[] = { 1,-1,0,0 };
 
char map[1002][1002] = { {'0',}, };
bool visit[1002][1002] = { {false,}, };
 
typedef struct {
    int y, x;
    char pos;
    int time;
}coordi;
 
 
int BFS(void) {
 
    for (int index = 0; index < h; index++) {
        for (int index_ = 0; index_ < w; index_++) {
            map[index][index_] = '0';
            visit[index][index_] = false;
        }
    }
    cin >> w >> h;
    for (int y = 0; y < h; y++) {
        cin >> map[y];
    }
    queue < coordi > Q;
    coordi start;
    for (int y = 0; y < h; y++) {
        for (int x = 0; x < w; x++) {
            
            if (map[y][x] == '@') {
                start.y = y;
                start.x = x;
                start.pos = '@';
                start.time = 0;
                if (y == h - 1 || y == 0 || x == w - 1 || x == 0) {
                    return 0;
                }
            }
            else if (map[y][x] == '*') {
                Q.push({ y ,x,'*',0 });
                visit[y][x] = true;
            }
            
        }
    }
    Q.push(start);
    while (!Q.empty()) {
 
        char now_pos = Q.front().pos;
        int now_x = Q.front().x;
        int now_y = Q.front().y;
        int time = Q.front().time;
 
        
        Q.pop();
 
        if (now_pos == '*') {
 
            for (int index = 0; index < 4; index++) {
                int nx = now_x + dx[index];
                int ny = now_y + dy[index];
                if (nx >= 0 && ny >= 0 && nx < w && ny < h) {
                    if (!visit[ny][nx]) {
                        if (map[ny][nx] != '#' && map[ny][nx] != '*') {
                            visit[ny][nx] = true;
                            map[ny][nx] = '*';
                            Q.push({ ny, nx, '*' , 0 });
                        }
                    }
                }
            }
        }
        else if (now_pos == '@') {
 
            for (int index = 0; index < 4; index++) {
                int nx = now_x + dx[index];
                int ny = now_y + dy[index];
                if (nx >= 0 && ny >= 0 && nx < w && ny < h) {
                    if (!visit[ny][nx]) {
                        if (map[ny][nx] == '.') {
                            if (nx == 0 || nx == w - 1 || ny == 0 || ny == h - 1) return time + 1;
                            visit[ny][nx] = true;
                            map[ny][nx] = '@';
                            Q.push({ ny, nx, '@',time + 1 });
                        }
                    }
                }
            }
        }
    }
    return -1;
}
 
 
int main(void) {
    cin >> N;
    int a[102];
    for (int index = 0; index < N; index++) {
        a[index] = BFS();
    }
    for (int index = 0; index < N; index++) {
        if (a[index]== -1) cout << "IMPOSSIBLE" << "\n";
        else cout << a[index]+1 << "\n";
    }
 
 
    return 0;
}

 

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