using System;
using System.Collections.Generic;
using System.Linq;

public class Program {
    public static string Solver(System.IO.TextReader reader) {
        const string PATTERN = "WBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBWBW";
        var buffer = reader.ReadLine().Split( ' ' );
        var w = int.Parse( buffer[ 0 ] );
        var h = int.Parse( buffer[ 1 ] );
        var c = char.Parse( buffer[ 2 ] );
        var writer = new System.IO.StringWriter();
        for (var i = 0; i != h; ++i) {
            writer.WriteLine( i % 2 == 0 ? ( c == 'W' ? PATTERN.Substring( 0, w ) : PATTERN.Substring( 1, w ) )
                : ( c == 'W' ? PATTERN.Substring( 1, w ) : PATTERN.Substring( 0, w ) ) );
        }
        return writer.ToString();
    }

    private static void Main() {
        Console.WriteLine( Solver( Console.In ) );
    }
}