AC日记——仙岛求药 openjude 2727

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

using namespace std;

#define maxm 10005

const int dx[5]={0,-1,0,1,0};
const int dy[5]={0,0,1,0,-1};

int n,m,quex[maxm],quey[maxm],qued[maxm];

char map[25][25];

bool if_[25][25];

int bfs()
{
    int sx,sy,h=0,tail=1;
    for(int i=1;i<=n;i++)
    {
        scanf("%s",map[i]+1);
        for(int j=1;j<=m;j++)
        {
            if_[i][j]=true;
            if(map[i][j]==‘@‘) sx=i,sy=j;
        }
    }
    quex[0]=sx,quey[0]=sy,qued[0]=0,if_[sx][sy]=false;
    while(h<tail)
    {
        int nowx=quex[h],nowy=quey[h],d=qued[h++];
        for(int i=1;i<=4;i++)
        {
            int x=nowx+dx[i],y=nowy+dy[i],dd=d+1;
            if(x>0&&x<=n&&y>0&&y<=m&&(map[x][y]==‘.‘||map[x][y]==‘*‘)&&if_[x][y])
            {
                if(map[x][y]==‘*‘) return dd;
                if_[x][y]=false;
                quex[tail]=x,quey[tail]=y,qued[tail++]=dd;
            }
        }
    }
    return -1;
}

int main()
{
    scanf("%d%d",&n,&m);
    while(n!=0&&m!=0) cout<<bfs()<<endl,scanf("%d%d",&n,&m);;
    return 0;
}