#include using namespace std; int main() { int a,b; char ch; bool x; int i,j;

cin>>a>>b;
cin>>ch;
cin>>x;

if(x)
{
    for(i=1; i<=a; i++)
    {
        for(j=1; j<=b; j++)   cout<<ch;
        cout<<endl;
    }
}
else
{
    for(i=1; i<=a; i++)
    {
        for(j=1; j<=b; j++)
        {
            if((i==1)||(i==a)||(j==1)||(j==b))//四条边均按条件输出
                cout<<ch;
            else
                cout<<" ";
        }
        cout<<endl;
    }
}
cout<<endl;
return 0;

}