using System;
using System.Collections.Generic;
using System.Text;

class Program
{
    public void Proc()
    {
        Reader.IsDebug = false;
        string[] inpt = Reader.ReadLine().Split(' ');
        int w = int.Parse(inpt[0]);
        int h = int.Parse(inpt[1]);
        char start = inpt[2][0];

        char[,] map =  new char[h,w];
        for (int i = 0; i < h; i++)
        {
            char bw = start;
            if (i > 0)
            {
                bw = Conv(map[i - 1, 0]);
            }
            for (int j = 0; j < w; j++)
            {
                map[i, j] = bw;
                bw = Conv(bw);
            }
        }

        for (int i = 0; i < h; i++)
        {
            StringBuilder sb = new StringBuilder();
            for (int j = 0; j < w; j++)
            {
                sb.Append(map[i, j]);
            }
            Console.WriteLine(sb.ToString());
        }
        
    
    }

    private char Conv(char prev)
    {
        if (prev == 'B')
        {
            return 'W';
        }
        else
        {
            return 'B';
        }
    }


    

    public class Reader
    {
        public static bool IsDebug = true;
        private static String PlainInput = @"


1 1 W



 
";
        private static System.IO.StringReader Sr = null;
        public static string ReadLine()
        {
            if (IsDebug)
            {
                if (Sr == null)
                {
                    Sr = new System.IO.StringReader(PlainInput.Trim());
                }
                return Sr.ReadLine();
            }
            else
            {
                return Console.ReadLine();
            }
        }
        public static int[] GetInt(char delimiter = ' ', bool trim = false)
        {
            string inptStr = ReadLine();
            if (trim)
            {
                inptStr = inptStr.Trim();
            }
            string[] inpt = inptStr.Split(delimiter);
            int[] ret = new int[inpt.Length];
            for (int i = 0; i < inpt.Length; i++)
            {
                ret[i] = int.Parse(inpt[i]);
            }
            return ret;
        }
    }
    static void Main()
    {
        Program prg = new Program();
        prg.Proc();
    }
}