import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class No00000082_Main {

	public static void main(String[] args) throws IOException {

		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		String[] bwArr = new String[]{"B","W"};
		String[] arr = br.readLine().split(" ");
		int subIndex = ("B".equals(arr[2])) ? 0 : 1;
		for(int i = 0; i < Integer.parseInt(arr[1]) ; i++) {
			for(int j = 0; j < Integer.parseInt(arr[0]) ; j++) {
				System.out.print(bwArr[(i + j + subIndex) %2]);
			}
			System.out.println();
		}
	}

}