#include<iostream>#include<cstdio>#include<cstdlib>#include<cstring>#include<string>#include<cmath>#include<map>#include<set>#include<vector>#include<algorithm>#include<stack>#include<queue>#include<cctype>#include<sstream>using namespace std;#define pii pair<int,int>#define LL long long intconst int eps=1e-8;const int INF=1000000000;const int maxnm=100+10;int ans,n,m,k,d[5][5];int dx[4]= {1,-1,0,0};int dy[4]= {0,0,1,-1};char maps[maxnm][maxnm];int had[maxnm][maxnm];struct Precious{    int x,y;    bool used;} p[5];int Bfs(int from,int to);bool Dfs(int id,int now,int step);void ini();int main(){    //freopen("in8.txt","r",stdin);    while(scanf("%d%d",&n,&m)==2)    {        if(n==0&&m==0) break;        ini();        for(int i=1; i<=n; i++)        {            for(int j=1; j<=m; j++)            {                cin>>maps[i][j];                if(maps[i][j]==‘@‘)                {                    p[0].x=i;                    p[0].y=j;                }            }        }        scanf("%d",&k);        for(int i=1; i<=k; i++)        {            int xx,yy;            scanf("%d%d",&xx,&yy);            p[i].x=xx;            p[i].y=yy;        }        if(Dfs(0,0,0))        {            printf("%d\n",ans);        }        else        {            printf("-1\n");        }    }    return 0;}void ini(){    memset(d,-1,sizeof(d));    ans=INF;    for(int i=0; i<5; i++)    {        p[i].used=0;    }}int Bfs(int from,int to){    if(d[from][to]!=-1) return d[from][to];    if((p[from].x==p[to].x)&&(p[from].y==p[to].y))    {        return d[from][to]=0;    }    else    {        queue<pii>q;        memset(had,0,sizeof(had));        q.push(make_pair(p[from].x,p[from].y));        had[p[from].x][p[from].y]=1;        while(!q.empty())        {            int tx=q.front().first;            int ty=q.front().second;            q.pop();            for(int i=0; i<4; i++)            {                int X=tx+dx[i];                int Y=ty+dy[i];                if(X>=1&&X<=n&&Y>=1&&Y<=m)                {                    if(had[X][Y]||maps[X][Y]==‘#‘)                    {                        continue;                    }                    else                    {                        q.push(make_pair(X,Y));                        had[X][Y]=had[tx][ty]+1;                        if(X==p[to].x&&Y==p[to].y)                        {                            return d[from][to]=had[X][Y]-1;                        }                    }                }            }        }        return d[from][to]=-2;    }}bool Dfs(int id,int now,int step)//id表示现在在哪点，now表示已经拿了几个，step表示目前一共走了几步{    bool w=0;    p[id].used=1;    if(now==k)    {        //cout<<"***"<<step<<endl;        ans=min(ans,step);        p[id].used=0;        return true;    }    else    {        for(int i=1; i<=k; i++)        {            if(p[i].used==0)            {                int stt=Bfs(id,i);                if(stt==-2)                {                    p[id].used=0;                    return false;                }                else                {                    if(Dfs(i,now+1,step+stt))                    {                        w=1;                    }                }            }        }        if(w==1)        {            p[id].used=0;            return true;        }        else        {            p[id].used=0;            return false;        }    }}