using System;
using System.Linq;

class Program
{
    public void Solve()
    {
        string[] WHC = Console.ReadLine().Split(' ');

        string[] color;
        if ("B".Equals(WHC[2])) { color = new string[] { "B", "W" }; }
        else { color = new string[] { "W", "B" }; }

        for (int i = 0; i < int.Parse(WHC[1]); i++)
        {
            for (int j = 0; j < int.Parse(WHC[0]); j++)
            {
                Console.Write(color[(i + j) % 2]);
            }
            Console.WriteLine();
        }
    }

    static void Main()
    {
        var solver = new Program();
        solver.Solve();
    }
}