#include <bits/stdc++.h>
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define RFOR(i,a,b) for(int i=(b) - 1;i>=(a);i--)
#define REP(i,n) for(int i=0;i<(n);i++)
#define RREP(i,n) for(int i=n-1;i>=0;i--)

#define PB push_back
#define INF INT_MAX/3
#define ALL(a) (a).begin(),(a).end()
#define CLR(a) memset(a,0,sizeof(a))

typedef long long int ll;

using namespace std;

int main(){
    int black[3] = {0};
    int blue[] = { 0,0,255 };
    int lime[] = {0,255,0};
    int aqua[] = {0,255,255};
    int red[] = {255,0,0};
    int fuchsia[] = {255,0,255};
    int yellow[] = {255,255,0};
    int white[] = {255,255,255};
    while(true){
	string s;
	cin >> s;
	if(s == "0") break;
	int rgb[3];
	rgb[0] = stoi(s.substr(1,2),nullptr,16);
	rgb[1] = stoi(s.substr(3,2),nullptr,16);
	rgb[2] = stoi(s.substr(5,2),nullptr,16);
	string ans;
	int m = 10000000;
	int sum = 0;
	REP(j,3) sum += (rgb[j]-black[j])*(rgb[j]-black[j]);
	if(m > sum){
	    m = sum;
	    ans = "black";
	}
	sum = 0;
	REP(j,3) sum += (rgb[j]-blue[j])*(rgb[j]-blue[j]);
	if(m > sum){
	    m = sum;
	    ans = "blue";
	}
	sum = 0;
	REP(j,3) sum += (rgb[j]-lime[j])*(rgb[j]-lime[j]);
	if(m > sum){
	    m = sum;
	    ans = "lime";
	}
	sum = 0;
	REP(j,3) sum += (rgb[j]-aqua[j])*(rgb[j]-aqua[j]);
	if(m > sum){
	    m = sum;
	    ans = "aqua";
	}
	sum = 0;
	REP(j,3) sum += (rgb[j]-red[j])*(rgb[j]-red[j]);
	if(m > sum){
	    m = sum;
	    ans = "red";
	}
	sum = 0;
	REP(j,3) sum += (rgb[j]-fuchsia[j])*(rgb[j]-fuchsia[j]);
	if(m > sum){
	m = sum;
	ans = "fuchsia";
	}
	sum = 0;
	REP(j,3) sum += (rgb[j]-yellow[j])*(rgb[j]-yellow[j]);
	if(m > sum){
	    m = sum;
	    ans = "yellow";
	}
	sum = 0;
	REP(j,3) sum += (rgb[j]-white[j])*(rgb[j]-white[j]);
	if(m > sum){
	    m = sum;
	    ans = "white";
	}
	cout << ans << endl;
    }
    return 0;
}