#include<iostream>
using namespace std;
int main()
{
	int a, b,f;
	char c;
	cin >> a >> b >> c >> f;
	if(f == 0)
	{
		
		for (int i = 0; i < b; i++)	cout << c ;
		cout << endl;
		for(int i = 1; i <= a-2; i++)
		{
			cout << c;
			for(int j = 1; j <= a-2; j++) cout << " ";
			cout << c << endl;
		}	
		
		for (int i = 0; i < b; i++) cout << c;	
		cout << endl;	
	}
	else
	{
		for (int i = 1; i <= a; i++)
		{
			for (int j = 1; j <= b; j++)
			cout << c;
		}
		cout << endl;
	}
    return 0;
}