广搜 迷宫(zznu 1962)

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<queue>

using namespace std;

#define N 110
#define met(a, b) memset(a, b, sizeof(a))

using namespace std;

const int dir[8][2] = {{-1,-1},{-1,0},{-1,1},{0,-1},{0,1},{1,-1,},{1,0},{1,1}};

struct node
{
    int x, y, step;
}JG[N];

int n, m, k, vis[N][N];
char G[N][N];

bool Judge(int x, int y)
{
    if(x>=1 && x<=n && y>=1 && y<=m && !vis[x][y] && (G[x][y]==‘.‘ || G[x][y]==‘@‘))
        return 1;
    return 0;
}

int BFS(int w)
{
    node p, q;
    p = JG[w];
    p.step = 0;

    queue<node>Q;
    Q.push(p);

    memset(vis, 0, sizeof(vis));
    vis[p.x][p.y] = 1;
    G[JG[w+1].x][JG[w+1].y] = ‘@‘;

    while(Q.size())
    {
        p = Q.front(); Q.pop();

        if(G[p.x][p.y]==‘@‘)
        {
            G[p.x][p.y] = ‘.‘;
            return p.step;
        }

        for(int i=0; i<8; i++)
        {
            q.x = p.x + dir[i][0];
            q.y = p.y + dir[i][1];
            q.step = p.step + 1;

            if(i==1 || i==3 || i==4 || i==6)
            {
                if(Judge(q.x, q.y))
                {
                    vis[q.x][q.y] = 1;
                    Q.push(q);
                }
            }
            else if(i==0)
            {
                if(Judge(q.x, q.y))
                {
                    if(G[p.x-1][p.y]==‘#‘ && G[p.x][p.y-1]==‘#‘) continue;
                    vis[q.x][q.y] = 1;
                    Q.push(q);
                }
            }
            else if(i==2)
            {
                if(Judge(q.x, q.y))
                {
                    if(G[p.x-1][p.y]==‘#‘ && G[p.x][p.y+1]==‘#‘) continue;
                    vis[q.x][q.y] = 1;
                    Q.push(q);
                }
            }
            else if(i==5)
            {
                if(Judge(q.x, q.y))
                {
                    if(G[p.x+1][p.y]==‘#‘ && G[p.x][p.y-1]==‘#‘) continue;
                    vis[q.x][q.y] = 1;
                    Q.push(q);
                }
            }
            else ///if(i==7)
            {
                if(Judge(q.x, q.y))
                {
                    if(G[p.x+1][p.y]==‘#‘ && G[p.x][p.y+1]==‘#‘) continue;
                    vis[q.x][q.y] = 1;
                    Q.push(q);
                }
            }

        }
    }
    return -1;
}

int main ()
{
    int t;

    scanf("%d", &t);

    while(t--)
    {
        int i, ans, sum=0;

        scanf("%d%d%d", &n, &m, &k);

        memset(G, 0, sizeof(G));

        for(i=1; i<=n; i++)
            scanf("%s", G[i]+1);

        scanf("%d%d", &JG[0].x, &JG[0].y);
        for(i=1; i<=k; i++)
        {
            scanf("%d%d", &JG[i].x, &JG[i].y);
            G[JG[i].x][JG[i].y] = ‘*‘;
        }

        if(G[JG[0].x][JG[0].y]==‘*‘ && k!=1)
        {
            printf("-1\n");
            continue;
        }

        for(i=0; i<k; i++) ///第i次查找
        {
            ans = BFS(i);
            if(ans==-1) break;
            sum += ans;
        }

        if(ans==-1) printf("-1\n");
        else        printf("%d\n", sum);
    }
    return 0;
}