#include <bits/stdc++.h>
using namespace std;
int a,b,f;
char c;
int main() 
{
	cin>>a>>b>>c>>f;
	if (f==1)
	{
		for (int i=1;i<=a;i++)
		{
			for (int j=1;j<=b;j++)
			{
				cout<<c;
			}
			cout<<endl;
		}
	}
	else
	{
		for (int i=1;i<=a;i++)
		{
			for (int j=1;j<=b;j++){
				if (i==1 || i==b || j==1 || j==b)
					cout<<c;
					else
						cout<<' ';
			}
			cout<<endl;
		}
		
	}
 	return 0;
}