[kuangbin带你飞]专题一 简单搜索- I - Fire Game

#include 
#include 
#include 
#include 
#include 
#include 
#include 
using namespace std;
#define INF 0x3f3f3f
int gcd(int a, int b) {return b==0 ? a:gcd(b,a%b);}

const int N = 15;
int n, m;
int flag;
int minn;
char s[N][N];
int vis[N][N];
int dis[N][N];
int xx[] = {0,0,-1,1};
int yy[] = {-1,1,0,0};

struct node
{
    int x, y;
};

struct no
{
    int x, y, step;
};

void bfs(int sx1, int sy1, int sx2, int sy2)
{
    for(int i = 1; i <= n; i++)
    {
        for(int j = 1; j <= m; j++) dis[i][j] = 0;
    }
    memset(vis,0,sizeof(vis));
    queue<no>q;
    int maxn = 0;
    if(sx1==sx2&&sy1==sy2){
        q.push((no){sx1,sy1,0});
        dis[sx1][sy1] = 0;
        vis[sx1][sy1] = 1;
    }else{
        q.push((no){sx1,sy1,0});
        q.push((no){sx2,sy2,0});
        dis[sx1][sy1] = 0;
        dis[sx2][sy2] = 0;
        vis[sx1][sy1] = 1;
        vis[sx2][sy2] = 1;
    }
    while(!q.empty())
    {
        no p = q.front(); q.pop();
        for(int i = 0; i < 4; i++)
        {
            int tx = p.x+xx[i];
            int ty = p.y+yy[i];
            if(tx<1||ty<1||tx>n||ty>m||vis[tx][ty]||s[tx][ty]=='.') continue;
            if(dis[tx][ty]>=p.step+1) continue;
            vis[tx][ty] = 1;
            dis[tx][ty] = p.step+1;
            maxn = max(maxn,dis[tx][ty]);
            q.push((no){tx,ty,p.step+1});
        }
    }
    int op = 1;
    for(int i = 1; i <= n; i++)
    {
        for(int j = 1; j <= m; j++)
        {
            if(s[i][j]=='#'&&vis[i][j]==0){
                op = 0;
                break;
            }
        }
        if(!op) break;
    }
    if(op){
        flag = 1;
        minn = min(minn,maxn);
    }
}

int main()
{
    int t;
    scanf("%d", &t);
    for(int tt = 1; tt <= t; tt++)
    {
        scanf("%d %d", &n, &m);
        for(int i = 1; i <= n; i++) scanf("%s", s[i]+1);
        printf("Case %d: ", tt);
        vector<node>a;
        for(int i = 1; i <= n; i++)
        {
            for(int j = 1; j <= m; j++)
            {
                if(s[i][j]=='#') a.push_back((node){i,j});
            }
        }
        flag = 0;
        minn = INF;
        int l = a.size();
        for(int i = 0; i < l; i++)
        {
            for(int j = i; j < l; j++)
            {
                bfs(a[i].x,a[i].y,a[j].x,a[j].y);
            }
        }
        if(!flag) printf("-1\n");
        else printf("%d\n", minn);
    }
    return 0;
}