#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <math.h>

int main()
{
	char str[2] = "";
	char start = 'W';
	int width = 0;
	int height = 0;

	scanf("%d", &width);
	scanf("%d", &height);
	scanf("%c", &start);

	for (int i = 0;i < height;i++)
	{
		for (int i = 0;i < width;i++)
		{
			printf("%c", start);
			if (start == 'W')
			{
				start = 'B';
			}
			else
			{
				start = 'W';
			}
		}
		if (width % 2 == 0)
		{
			if (start == 'W')
			{
				start = 'B';
			}
			else
			{
				start = 'W';
			}
		}
		printf("\n");
	}

	return 0;
}