#include <iostream>
#include <vector>
#include <string>
using namespace std;

template<class T>
T sqr(T obj) {return obj * obj;}

struct color {
	string name;
	int R, G, B;

	color(string n, int r, int g, int b) {
		name = n;
		R = r;
		G = g;
		B = b;
	}
};

color color_list[] = {
	color("black", 0x00, 0x00, 0x00),
	color("blue", 0x00, 0x00, 0xff),
	color("lime", 0x00, 0xff, 0x00),
	color("aqua", 0x00, 0xff, 0xff),
	color("red", 0xff, 0x00, 0x00),
	color("fuchsia", 0xff, 0x00, 0xff),
	color("yellow", 0xff, 0xff, 0x00),
	color("white", 0xff, 0xff, 0xff),
};

int main() {
	string s;
	while(cin >> s) {
		if(s[0] == '0')
			break;

		int mind, indx;
		indx = 0;
		mind = 1e8;

		int a[3];
		for(int j = 0; j < 3; j++) {
			int tmp = 0;
			if('0' <= s[1 + 2 * j] && s[1 + 2 * j] <= '9')
				tmp += (s[1 + 2 * j] - '0') * 16;
			else
				tmp += (s[1 + 2 * j] - 'a' + 10) * 16;

			if('0' <= s[2 + 2 * j] && s[2 + 2 * j] <= '9')
				tmp += (s[2 + 2 * j] - '0');
			else
				tmp += (s[2 + 2 * j] - 'a' + 10);
			a[j] = tmp;
		}

		for(int i = 0; i < 8; i++) {
			int d = 0;

			d += sqr(color_list[i].R - a[0]);
			d += sqr(color_list[i].G - a[1]);
			d += sqr(color_list[i].B - a[2]);
			if(d < mind) {
				indx = i;
				mind = d;
			}
		}
		cout << color_list[indx].name << endl;
	}
}