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

int main()
{
    string str;
    string s[8] = {"black","blue","lime","aqua","red","fuchsia","yellow","white"};
    int a[150] = {};
    int b[8][3];

    for( int i = '0'; i < '0' + 10; i++ )
        a[i] = i - '0';
    for( int i = 'a'; i < 'a' + 6; i++ )
        a[i] = i - 'a' + 10;

    for( int i = 0; i < 8; i++ )
    {
        if( i / 4 == 0 )
            b[i][0] = 0;
        else
            b[i][0] = 255;

        if( i == 0 || i == 1 || i == 4 || i == 5 )
            b[i][1]= 0;
        else
            b[i][1] = 255;   

        if( i % 2 == 0 )
            b[i][2] = 0;
        else
            b[i][2] = 255;
    }

    while( cin >> str )
    {
        if( str == "0" )
            break;
            
        int r = a[str[1]] * 16 + a[str[2]], g = a[str[3]] * 16 + a[str[4]], d = a[str[5]] * 16 + a[str[6]];
        int res = 0;
        int min = 100000000;
        for( int i = 0; i < 8; i++ )
        {
            if( ( b[i][0] - r ) * ( b[i][0] - r ) + ( b[i][1] - g ) * ( b[i][1] - g ) + ( b[i][2] - d ) * ( b[i][2] - d ) < min )
            {
                min = ( b[i][0] - r ) * ( b[i][0] - r ) + ( b[i][1] - g ) * ( b[i][1] - g ) + ( b[i][2] - d ) * ( b[i][2] - d );
                res = i;
            }
        }
        cout << s[res] << endl;
    }


    return 0;
}

