#include<iostream.h>
using namespace std ;
int main (){ int n,i,j;
char c,d;
cin>>n;
cin>>c;
cin>>d;
for(i=1;i<=n;i++) //Se afiseaza prima linie de c
cout<<c;
cout<<endl;
for(i=2;i<=n-1;i++){
cout<<c;
for(j=2;j<=n-1;j++)
cout<<d;
cout<<c;
cout<<endl; }
for(i=1;i<=n;i++) //Se afiseaza ultimul rand de c-uri
cout<<c;