HDU_1241

#include<cstdio>
#include<cstring>
using namespace std;
const int maxn = 100 + 5;

char pic[maxn][maxn];
int m, n, idx[maxn][maxn];

void dfs(int r, int c, int id) {
    if(r < 0 || r >= m || c < 0 || c >= n) return;
    if(idx[r][c] > 0 || pic[r][c] != '@') return;
    idx[r][c] = id;
    for(int dr = -1; dr <= 1; dr++)
        for(int dc = -1; dc <= 1; dc++)
            if(dr != 0 || dc != 0) dfs(r+dr, c+dc, id);
}
int main() {
    while(scanf("%d%d", &m, &n) == 2 && m && n) {
        for(int i = 0; i < m; i++) scanf("%s", pic[i]);
        memset(idx, 0, sizeof(idx));
        int cnt = 0;
        for(int i = 0; i < m; i++)
            for(int j = 0; j < n; j++)
                if(idx[i][j] == 0 && pic[i][j] == '@') dfs(i, j, ++cnt);
        printf("%d\n", cnt);
    }
    return 0;
}

HDU_1241

原文：http://blog.csdn.net/czkct/article/details/45649511