UVA 572 - Oil Deposits

这道题是一道搜索题，要我们找有多少块不同的油田，@与其相邻的八个方向的@属于同一片油田，

我选择用dfs来做。

#include<stdio.h>
#include<string.h>
#define N 105
int map[N][N], vis[N][N];
char str[N];

int dx[] = { -1, 1, 0, 0, -1, -1, 1, 1};
int dy[] = { 0, 0, -1, 1, -1, 1, -1, 1};

void dfs( int x, int y)
{
    int newx, newy;
    for( int i = 0; i < 8; i ++)
    {
        newx = x + dx[i];
        newy = y + dy[i];
        if( map[newx][newy] && !vis[newx][newy])
        {
            vis[newx][newy] = 1;
            dfs(newx, newy);
        }
    }
}

int main()
{
    int m, n;
    int i, j;
    while( scanf( "%d%d", &m, &n) != EOF)
    {
        if( m == 0 && n == 0) break;
        memset( map, 0, sizeof(map) );
        memset( vis, 0, sizeof(vis) );
        for( i = 1; i <= m; i ++)
        {
            scanf( "%s", str + 1);
            for( j = 1; j <= n; j ++)
            {
                if( str[j] == '@')
                    map[i][j] = 1;
            }
        }
        int cnt = 0;
        for( i = 1; i <= m; i ++)
            for( j = 1; j <= n; j ++)
            {
                if( map[i][j] && !vis[i][j])
                {
                    cnt ++;
                    vis[i][j] = 1;
                    dfs( i, j);
                }
            }
        printf( "%d\n", cnt);
    }
    return 0;
}