#include <bits/stdc++.h>
using namespace std;

namespace
{
const char *S = "WBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWB";
char A[ 100 ];
char B[ 100 ];
}

int main()
{
int i;
int H;
int W;
char C;

	cin >> W;
	cin >> H;
	cin >> C;

	if( C == 'B' )
	{
		strcpy( A, S + 1 );
		A[ W ] = '\0';
		strcpy( B, S );
		B[ W ] = '\0';
	}
	else
	{
		strcpy( A, S );
		A[ W ] = '\0';
		strcpy( B, S + 1 );
		B[ W ] = '\0';
	}

	for( i = 0; i < H; i++ )
	{
		if( i % 2 == 0 )
			cout << A << endl;
		else
			cout << B << endl;
	}

	return 0;
}