# include "bits/stdc++.h"
using namespace std;
using LL = long long;
using ULL = unsigned long long;
const double PI = acos(-1);
template<class T>constexpr T INF() { return ::std::numeric_limits<T>::max(); }
template<class T>constexpr T HINF() { return INF<T>() / 2; }
template <typename T_char>T_char TL(T_char cX) { return tolower(cX); };
template <typename T_char>T_char TU(T_char cX) { return toupper(cX); };
typedef pair<LL, LL> pii;
const int vy[] = { -1, -1, -1, 0, 1, 1, 1, 0 }, vx[] = { -1, 0, 1, 1, 1, 0, -1, -1 };
const int dx[4] = { 0,1,0,-1 }, dy[4] = { 1,0,-1,0 };
int popcnt(unsigned long long n) { int cnt = 0; for (int i = 0; i < 64; i++)if ((n >> i) & 1)cnt++; return cnt; }
int d_sum(LL n) { int ret = 0; while (n > 0) { ret += n % 10; n /= 10; }return ret; }
int d_cnt(LL n) { int ret = 0; while (n > 0) { ret++; n /= 10; }return ret; }
LL gcd(LL a, LL b) { if (b == 0)return a; return gcd(b, a%b); };
LL lcm(LL a, LL b) { LL g = gcd(a, b); return a / g*b; };
# define ALL(qpqpq)           (qpqpq).begin(),(qpqpq).end()
# define UNIQUE(wpwpw)        sort(ALL((wpwpw)));(wpwpw).erase(unique(ALL((wpwpw))),(wpwpw).end())
# define LOWER(epepe)         transform(ALL((epepe)),(epepe).begin(),TL<char>)
# define UPPER(rprpr)         transform(ALL((rprpr)),(rprpr).begin(),TU<char>)
# define FOR(i,tptpt,ypypy)   for(LL i=(tptpt);i<(ypypy);i++)
# define REP(i,upupu)         FOR(i,0,upupu)
# define INIT                 std::ios::sync_with_stdio(false);std::cin.tie(0)


string color[]={"black","blue","lime","aqua","red","fuchsia","yellow","white"};
int red[]={0,0,0,0,255,255,255,255};
int green[]={0,0,255,255,0,0,255,255};
int blue[]={0,255,0,255,0,255,0,255};

string s;
int r,g,b;

int trance(char c){
    if('0'<=c&&c<='9')return c-'0';
    else return c-'a'+10;
}

int main(){
    while(cin>>s&&s!="0"){
        r=trance(s[1])*16+trance(s[2]);
        g=trance(s[3])*16+trance(s[4]);
        b=trance(s[5])*16+trance(s[6]);
        string ret;
        double num=INF<double>();
        REP(i,8){
            double num2=sqrt((r-red[i])*(r-red[i])+(g-green[i])*(g-green[i])+(b-blue[i])*(b-blue[i]));
            if(num>=num2){
                num=num2;
                ret=color[i];
            }
        }
        cout<<ret<<endl;
    }
}
