hdu 6699 Block Breaker BFS

每次从敲掉的位置开始bfs就行了，因为敲掉一个方块，只会直接影响其周边的方块，一层层bfs就能找出所有的跌落方块。

#include <cstdio>
#include <queue>
using namespace std;
queue <int> que[2];
int n,m,q,T;
int mx[] = {-1,1,0,0},my[] = {0,0,-1,1};
bool hav[2050][2050];
bool drp(int nx,int ny)
{
    if (hav[nx][ny] == false)
        return false;
    if (nx > n || nx < 1 || ny > m || ny < 1)
        return false;
    if ((hav[nx - 1][ny] && hav[nx + 1][ny]) || (hav[nx][ny - 1] && hav[nx][ny + 1]))
        return false;
    return true;
}
int bfs(int sx,int sy)
{
    if (hav[sx][sy] == false)
        return 0;
    int res = 1;
    que[0].push(sx);
    que[1].push(sy);
    hav[sx][sy] = false;
    while (que[0].empty() == false)
    {
        int tx = que[0].front();
        int ty = que[1].front();
        que[0].pop();
        que[1].pop();
        for (int i = 0;i <= 3;i++)
        {
            int nx = tx + mx[i];
            int ny = ty + my[i];
            if (drp(nx,ny) == true)
            {
                hav[nx][ny] = false;
                res++;
                que[0].push(nx);
                que[1].push(ny); 
            }
        }
    }
    return res;
}
int main()
{
    for (scanf("%d",&T); T != 0; T--)
    {
        scanf("%d%d%d",&n,&m,&q);
        for (int i = 0;i <= n + 1;i++)
            for (int j = 0;j <= m + 1;j++)
                hav[i][j] = true;
        int tx,ty;
        for (int i = 1; i <= q; i++)
        {
            scanf("%d%d",&tx,&ty);
            printf("%d
",bfs(tx,ty));
        }
    }
    return 0;
}