#include <bits/stdc++.h>

using namespace std;

string colors[8] = {
  "black", "blue", "lime", "aqua", "red", "fuchsia", "yellow", "white"
};

int c(char ch) {
  if(isdigit(ch)) return ch-'0';
  return ch-'a'+10;
}

int d(string s) {
  return c(s[0])*16 + c(s[1]);
}

int main() {
  
  int colR[8];
  int colG[8];
  int colB[8];
  
  colR[0] = d("00"); colG[0] = d("00"); colB[0] = d("00");
  colR[1] = d("00"); colG[1] = d("00"); colB[1] = d("ff");
  colR[2] = d("00"); colG[2] = d("ff"); colB[2] = d("00");
  colR[3] = d("00"); colG[3] = d("ff"); colB[3] = d("ff");
  colR[4] = d("ff"); colG[4] = d("00"); colB[4] = d("00");
  colR[5] = d("ff"); colG[5] = d("00"); colB[5] = d("ff");
  colR[6] = d("ff"); colG[6] = d("ff"); colB[6] = d("00");
  colR[7] = d("ff"); colG[7] = d("ff"); colB[7] = d("ff");
  
  /*
  for(int i=0; i<8; i++) {
    colR[i] = i & 1 ? 255 : 0;
    colG[i] = i & 2 ? 255 : 0;
    colB[i] = i & 4 ? 255 : 0;
  }
  */
  
  string s;
  
  while(cin >> s) {
    if(s == "0") break;
    
    s = s.substr(1);
    
    int R = d(s.substr(0, 2));
    int G = d(s.substr(2, 2));
    int B = d(s.substr(4, 2));
    
    int minD = (int)1e9;
    int id = -1;
    for(int i=0; i<8; i++) {
      if( minD > pow(R-colR[i],2.0) + pow(G-colG[i],2.0) + pow(B-colB[i],2.0) ) {
	id = i;
	minD = pow(R-colR[i],2.0) + pow(G-colG[i],2.0) + pow(B-colB[i],2.0);
      }
    }
    
    cout << colors[id] << endl;
  }
  
  return 0;
}