import std.stdio, std.array, std.string, std.conv, std.algorithm;
import std.typecons, std.range, std.random, std.math, std.container;
import std.numeric, std.bigint, core.bitop;


void main() {
    auto s = readln.split.map!(to!int);
    auto H = s[0];
    auto W = s[1];
    auto D = s[2];

    char[][] ans = new char[][](H);
    string[] cl = ["RG", "BY"];

    foreach (i; 0..H) {
        foreach (j; 0..W) {
            int k = i / D % 2;
            int x = i / (2 * D) % 2;
            ans[i] ~= cl[k][(j+x)%2];
        }
    }

    ans.each!writeln;
}
