POJ 1562 Oil Deposits

#include <iostream>
#include <cstdio>
#include <cstring>
#define REP(i, s, n) for(int i = s; i <= n; i ++)
#define REP_(i, s, n) for(int i = n; i >= s; i --)
#define MAX_N 100 + 10

using namespace std;

int n, m, ans = 0;
bool map[MAX_N][MAX_N];
int dx[9] = {0, -1, -1, -1, 0, 0, 1, 1, 1}, dy[9] = {0, -1, 0, 1, -1, 1, -1, 0, 1};

void dfs(int x, int y){
    map[x][y] = 0;
    REP(i, 1, 8){
        int nx = x + dx[i], ny = y + dy[i];
        if(map[nx][ny] && nx >= 1 && nx <= n && ny >= 1 && ny <= m)
            dfs(nx, ny);
    }
}

int main(){
    freopen("1.in", "r", stdin);
    char c;
    while(scanf("%d%d", &n, &m) != EOF){
        if(n == 0 && m == 0) break;
        getchar();
        REP(i, 1, n){
            REP(j, 1, m){
                cin >> c;
                map[i][j] = (c == ‘@‘ ? 1 : 0);
            }getchar(); 
        }

        ans = 0;
        REP(i, 1, n) REP(j, 1, m){
            if(map[i][j]) ans ++, dfs(i, j);
        }

        printf("%d\n", ans);
    }
    return 0;
}