#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <complex>
#include <cstring>
#include <cstdlib>
#include <string>
#include <cmath>
#include <queue>
using namespace std;

#define REP(i,n) for(int i=0;i<(int)n;++i)
#define FOR(i,c) for(__typeof((c).begin())i=(c).begin();i!=(c).end();++i)
#define ALL(c) (c).begin(), (c).end()
#define INF 1<<30

int main() {
  string color[] = {"black", "blue", "lime", "aqua", "red", "fuchsia", "yellow", "white"};
  string s;
  while(cin >> s, s!="0") {
    int rgb[3];
    REP(i,3)
      sscanf(s.substr(i*2+1,2).c_str(), "%x", rgb+i);
    
    int mi = INF;
    int ans;
    REP(i,8) {
      int hoge = 0;
      REP(j,3) {
        if (i>>j & 1)
          hoge += pow(255 - rgb[j], 2);
        else
          hoge += pow(rgb[j], 2);
      }
      if (hoge < mi) {
        mi = hoge;
        ans = i;
      }
    }
    cout << color[ans] << endl;
  }
}