1 #include<iostream>
  2 #include<cstring>
  3 #include<cstdlib>
  4 #include<cstdio>
  5 #include<algorithm>
  6 #include<cmath>
  7 #include<queue>
  8 #include<map>
  9 #include<string>
 10 
 11 #define N 105
 12 #define M 15
 13 #define mod 10000007
 14 //#define p 10000007
 15 #define mod2 100000000
 16 #define ll long long
 17 #define LL long long
 18 #define maxi(a,b) (a)>(b)? (a) : (b)
 19 #define mini(a,b) (a)<(b)? (a) : (b)
 20 
 21 using namespace std;
 22 
 23 int ans;
 24 int n,m;
 25 int k;
 26 char s[N][N];
 27 int a[N][N];
 28 int mi[20][N][N];
 29 int dirx[]={1,0,-1,0};
 30 int diry[]={0,1,0,-1};
 31 
 32 typedef struct
 33 {
 34     int x;
 35     int y;
 36     int step;
 37     int st;
 38 }PP;
 39 
 40 PP start;
 41 
 42 void ini()
 43 {
 44     ans=-1;
 45     int i,j,p;
 46     int x,y;
 47     for(i=0;i<n;i++){
 48         scanf("%s",s[i]);
 49     }
 50     memset(a,0,sizeof(a));
 51     scanf("%d",&k);
 52     for(i=0;i<n;i++){
 53         for(j=0;j<m;j++){
 54             for(p=0;p<(1<<k);p++){
 55                 mi[p][i][j]=1000000000;
 56             }
 57             if(s[i][j]==‘@‘){
 58                 start.x=i;
 59                 start.y=j;
 60                 start.st=0;
 61                 start.step=0;
 62             }
 63             if(s[i][j]==‘#‘){
 64                 a[i][j]=-1;
 65             }
 66         }
 67     }
 68     for(i=0;i<k;i++){
 69         scanf("%d%d",&x,&y);
 70         a[x-1][y-1]=(1<<i);
 71         if(x-1==start.x && y-1==start.y){
 72             start.st+=(1<<i);
 73             mi[start.st][start.x][start.y]=0;
 74         }
 75     }
 76     if(start.st==0){
 77         mi[0][start.x][start.y]=0;
 78     }
 79 
 80    // for(i=0;i<n;i++){
 81     //    for(j=0;j<m;j++){
 82     //        printf(" %d",a[i][j]);
 83     //    }printf("\n");
 84    // }
 85 }
 86 
 87 int ok(int i,int j)
 88 {
 89     if(i>=0 && i<n && j>=0 && j<m && a[i][j]!=-1){
 90         return 1;
 91     }
 92     return 0;
 93 }
 94 
 95 void solve()
 96 {
 97     int i;
 98     PP now,nx;
 99     queue<PP> q;
100     q.push(start);
101     while(q.size()>=1)
102     {
103 
104         now=q.front();
105       //  printf(" i=%d j=%d st=%d step=%d\n",now.x,now.y,now.st,now.step);
106         q.pop();
107         if(now.st== ((1<<k)-1) ){
108             ans=now.step;return;
109         }
110 
111         for(i=0;i<4;i++){
112             nx=now;
113             nx.step++;
114             nx.x=now.x+dirx[i];
115             nx.y=now.y+diry[i];
116             if(ok(nx.x,nx.y)==0) continue;
117             if( (now.st & a[nx.x][nx.y])==0){
118                 nx.st=(now.st ^ a[nx.x][nx.y]);
119                // printf("  %d %d %d\n",now.st, a[nx.x][nx.y],nx.st);
120                 //q.push(nx);
121               //  mi[nx.st][nx.x][nx.y]=min(nx.step,mi[nx.st][nx.x][nx.y]);
122             }
123             //else{
124                 if( nx.step< mi[nx.st][nx.x][nx.y]){
125                     q.push(nx);
126                     mi[nx.st][nx.x][nx.y]=nx.step;
127                 }
128            // }
129         }
130     }
131 }
132 
133 
134 void out()
135 {
136     printf("%d\n",ans);
137 }
138 
139 int main()
140 {
141     //freopen("data.in","r",stdin);
142     //freopen("data.out","w",stdout);
143     //scanf("%d",&T);
144    // for(int ccnt=1;ccnt<=T;ccnt++)
145    // while(T--)
146     while(scanf("%d%d",&n,&m)!=EOF)
147     {
148         if(n==0 && m==0 ) break;
149         //printf("Case %d: ",ccnt);
150         ini();
151         solve();
152         out();
153     }
154 
155     return 0;
156 }