import std.algorithm;
import std.array;
import std.ascii;
import std.bigint;
import std.complex;
import std.container;
import std.conv;
import std.functional;
import std.math;
import std.range;
import std.stdio;
import std.string;
import std.typecons;

auto readInts() {
	return array(map!(to!int)(readln().strip().split()));
}
auto readInt() {
	return readInts()[0];
}
auto readLongs() {
	return array(map!(to!long)(readln().strip().split()));
}
auto readLong() {
	return readLongs()[0];
}

void readlnTo(T...)(ref T t) {
    auto s = readln().split();
    assert(s.length == t.length);
    foreach(ref ti; t) {
        ti = s[0].to!(typeof(ti));
        s = s[1..$];
    }
}

const real eps = 1e-10;

const long p = 1_000_000_000 + 7;

int diff(in int[] a, in int[] b) {
    return reduce!((a, b) => a + pow(b[1]-b[0], 2))(0, zip(a, b));
}

string calc(string l) {
    auto color = [
        "black": [0, 0, 0],
        "blue": [0, 0, 0xff],
        "lime": [0, 0xff, 0],
        "aqua": [0, 0xff, 0xff],
        "red": [0xff, 0, 0],
        "fuchsia": [0xff, 0, 0xff],
        "yellow": [0xff, 0xff, 0],
        "white": [0xff, 0xff, 0xff]
    ];

        auto r = to!int(l[1..3], 16);
        auto g = to!int(l[3..5], 16);
        auto b = to!int(l[5..7], 16);
        string ans = "black";
        foreach(name, value; color) {
            if(diff(value, [r, g, b]) < diff(color[ans], [r, g, b])) {
                ans = name;
            }
        }
        return ans;
}

void main(){
    while(true) {
        auto l = readln().chomp();
        if(l == "0") {
            return;
        }
        writeln(calc(l));
    }
}