[백준 4963번] 섬의 개수

소스코드

---

#include <iostream>
using namespace std;
 
typedef struct{
    int x, y;
}QUE;
int xpos[8] = { -1, -1, -1, 0, 0, 1, 1, 1 };
int ypos[8] = { -1, 0, 1, -1, 1, -1, 0, 1 };
 
int main() {
    while (1) {
        int w, h, map[51][51], visit[51][51],cnt=3;
        cin >> w >> h;
        if (!w&&!h)
            return 0;
        for (int i = 0; i < h; i++)
            for (int j = 0; j < w; j++) {
                cin >> map[i][j];
                visit[i][j] = 0;
            }
        QUE q[10001];
        for (int i = 0; i < h; i++)
            for (int j = 0; j < w; j++) {
                int hh = 0, tt = 0;
                if (map[i][j]==1) {
                    q[tt].x = i, q[tt++].y = j;
                    while (hh != tt){
                        int curx = q[hh].x;
                        int cury = q[hh++].y;
                        for (int a = 0; a < 8; a++) {
                            if (curx + xpos[a] < 0 || curx + xpos[a] >= h || cury + ypos[a] < 0 || cury + ypos[a] >= w)
                                continue;
                            if (map[curx + xpos[a]][cury + ypos[a]] && !visit[curx + xpos[a]][cury + ypos[a]]) {
                                visit[curx + xpos[a]][cury + ypos[a]] = 1;
                                map[curx + xpos[a]][cury + ypos[a]] = cnt;
                                q[tt].x = curx + xpos[a];
                                q[tt++].y = cury + ypos[a];
                            }
                        }
                    }
                    cnt++;
                }
            }
        cout << cnt-3 << '\n';
    }
    return 0;
}