#include

using namespace std;

int main(){
    int n,m;
    cin>>n>>m;
    // bool is = true;
    for(int i=1;i<=n;i++){
        if(i%4==2){
            for(int i=1;i                cout<<".";
            }
            cout<<"#";
        }else if(i%4==0){
           cout<<"#";
           for(int i=1;i                cout<<".";
            } 
        }else{
            for(int i=1;i<=m;i++){
                cout<<"#";
            }
        }
        cout<<"\n";
    }
    return 0;
}