#include <bits/stdc++.h>
using namespace std;
int n , m , k ;
char c[21][21] ;
char perm[21][21] ;
vector< pair<int , int > > path[21][21] ;
set< pair<int , int > > tunnel ;
int startx , starty , endx , endy ;
bool inside( int x , int y ){
    return x>=1 and y>=1 and x<=n and y<=m ;
}
bool not_tunnel( int x , int y ){
    return tunnel.find( make_pair(x,y) ) == tunnel.end()  ;
}
pair< double , double > find_ans( int x , int y , set< pair< int , int > >nonset , pair<int , int > pp) ;
int main() {
    cin >> n >> m >> k ;
    for( int i=1 ; i<=n ; i++ ){
        for( int j=1 ; j<=m ; j++){
            cin >> c[i][j] ;
            perm[i][j]=c[i][j] ;
            if( c[i][j]=='*' ){
                c[i][j]='O' ;
            }
            if( c[i][j]=='A' ){
                startx = i ; 
                starty = j ;
                c[i][j]='O' ;
            }
            else if( c[i][j]=='%' ){
                endx = i ;
                endy = j ;
                c[i][j]='O' ;
            }
        }
    }
    while( k-- ){
        int x1 , y1 , p1 , q1 ;
        cin >> x1 >> y1 >> p1 >> q1 ;
        tunnel.insert( make_pair(x1,y1) ) ;
        tunnel.insert( make_pair(p1 , q1) ) ;
        path[x1][y1].push_back( make_pair(p1,q1) ) ;
        path[p1][q1].push_back( make_pair(x1,y1) ) ;
    }
    for( int i=1 ; i<=n ; i++ ){
        for( int j=1 ; j<=m ; j++){          
            if( c[i][j] == 'O' and not_tunnel(i,j) ){    //cout<<" for " <<i<<" , "<<j<<endl ;
                if( c[i-1][j]=='O' and inside(i-1,j) ){
                    path[i][j].push_back(make_pair(i-1,j)) ;  // cout<<" push{"<<i-1<<","<<j<<endl ;
                }
                if( c[i+1][j]=='O' and inside(i+1,j) ){
                    path[i][j].push_back(make_pair(i+1,j)) ;        //cout<<" push{"<<i+1<<","<<j<<endl ;
                }
                if( c[i][j-1]=='O' and inside(i,j-1) ){
                    path[i][j].push_back( make_pair(i,j-1) ) ;        // cout<<" push{"<<i<<","<<j-1<<endl ;
                }
                if( c[i][j+1]=='O' and inside(i,j+1) ){
                    path[i][j].push_back( make_pair(i,j+1) ) ;            //    cout<<" push{"<<i<<","<<j+1<<endl ;
                }
            }
        }
    }
    set< pair< int , int > > nonset ;
    pair< double , double > p = find_ans(startx , starty , nonset , make_pair(-1 , -1 ) ) ;
    cout<< (p.first/p.second) <<endl ;
    return 0;
}
pair< double , double > find_ans( int x , int y , set< pair< int , int > >nonset , pair<int , int > pp){
    set< pair< int , int > > temp_set ;
    temp_set.insert( pp ) ;
    set< pair< int , int > > :: iterator it = nonset.begin() ;
    while( it!= nonset.end() ){
        temp_set.insert( *it ) ;
        it++ ;
    }                                                  //          cout<<" came for "<<x<<","<<y<<endl ;
    temp_set.insert( make_pair( x , y) ) ;
    if( perm[x][y]=='*' ){
        return make_pair(0,1) ;
    }
    else if( perm[x][y]=='%' ){
        return make_pair(1,1) ;
    }
    int cnt = 0 ;
    for( int i=0 ; i<path[x][y].size() ; i++){
        pair<int , int > p = path[x][y][i] ;
        if( temp_set.find(p) == temp_set.end() ){
            cnt++ ;
        }
    }
    double factor = 1.0/(cnt*1.0) ;
    pair< double , double > ans = make_pair( 0 , 1 ) ;
    for( int i=0 ; i<path[x][y].size() ; i++){
        pair<int , int > p = path[x][y][i] ;
        if(temp_set.find(p) == temp_set.end() ){
            ans.first += ( factor* (find_ans(p.first,p.second,temp_set , p) ).first ) ; 
        }
    }
    return ans ;
}