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

using namespace std;

typedef vector<int> vi;
typedef vector<vi> vii;
typedef vector<string> vs;
typedef vector<bool> vb;
typedef vector<vb> vbb;
typedef pair<int, int> pii;
typedef long long ll;
typedef unsigned long long ull;

#define all(a)  (a).begin(),(a).end()
#define rall(a) (a).rbegin(), (a).rend()
#define pb push_back
#define mp make_pair

#define loop(i,a,b) for(int i=(a);i<ull(b);++i)
#define rep(i,n) loop(i,0,n)

const double eps = 1e-10;
const double pi  = acos(-1.0);
const double inf = (int)1e8;

string color[8] = {"black", "blue", "lime", "aqua", "red", "fuchsia", "yellow", "white"};
string strength[8] = {"000000", "0000ff", "00ff00", "00ffff", "ff0000", "ff00ff", "ffff00", "ffffff"};

int toi(string s){
    int ret = 0;
    rep(i, s.size()){
        string t = s.substr(i, 1);
        if('0' <= t[0] && t[0] <= '9') ret += stoi(t);
        else ret += t[0]-'a'+10;
        if(i != s.size()-1) ret *= 16;
    }
    return ret;
}

vector<int> rgb(string s){
    vi ret;
    rep(i, 3){
        string t = s.substr(i*2, 2);
        ret.pb(toi(t));
    }
    return ret;
}

int main(){
    string  s;
    while(cin >> s, s!="0"){
        s = s.substr(1);
        vi c = rgb(s);
        double m = inf;
        int ans = 0;
        rep(i, 8){
            vi d = rgb(strength[i]);
            double ret = sqrt(pow(c[0]-d[0], 2)+pow(c[1]-d[1], 2)+pow(c[2]-d[2], 2));
            if(m > ret){ans = i; m = ret;}
        }
        cout << color[ans] << endl;
    }
}