#include <iostream>
#include <cmath>
#include <algorithm>
#include <string>
#include <vector>

using namespace std;

class color{
public:
	int r,g,b;
	string name;
	color(int x,int y,int z){r=x;g=y;b=z;}
	color(string s,int x, int y, int z){name = s; r=x; g=y; b=z;}

	double dist(const color arg){
		return sqrt(pow(abs(r - arg.r),2) +
				pow(abs(g - arg.g),2) +
				pow(abs(b - arg.b),2));
	}
};

int c2d(char c){
	if('a' <= c && c <= 'f'){
		return c - 'a' + 10;
	}else{
		return c - '0';
	}
}

int main(void){
	string str;
	vector<color> co;
	co.push_back(color("black",0,0,0));
	co.push_back(color("blue",0,0,255));
	co.push_back(color("lime",0,255,0));
	co.push_back(color("aqua",0,255,255));
	co.push_back(color("red",255,0,0));
	co.push_back(color("fuchsia",255,0,255));
	co.push_back(color("yellow",255,255,0));
	co.push_back(color("white",255,255,255));
	while(cin >> str){
		if(str[0] == '0') break;
		int c[3] = {0,0,0};
		char tmp;
		double dist = 1 << 30;
		int index;
		for(int i=0;i<3;i++){
			c[i] += c2d(str[i*2+1]) * 16;
			c[i] += c2d(str[i*2+2]);
		}
		color arg = color(c[0],c[1],c[2]);

		for(int i=0;i<8;i++){
			double tdist = co[i].dist(arg);
			if(dist > tdist){
				dist = tdist;
				index = i;
			}
		}
		cout << co[index].name << endl;
	}
}