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

struct Color {
    string name; int r, g, b;
};
vector<Color> colors = {
    (Color){"black", 0, 0, 0},
    (Color){"blue", 0, 0, 255},
    (Color){"lime", 0, 255, 0},
    (Color){"aqua", 0, 255, 255},
    (Color){"red", 255, 0, 0},
    (Color){"fuchsia", 255, 0, 255},
    (Color){"yellow", 255, 255, 0},
    (Color){"white", 255, 255, 255}
};

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

int sq(int x) {
    return x * x;
}

int main() {
    string s;
    while (cin >> s, s != "0") {
        int r = dec(s[1]) * 16 + dec(s[2]);
        int g = dec(s[3]) * 16 + dec(s[4]);
        int b = dec(s[5]) * 16 + dec(s[6]);
        int mn = INT_MAX, k = -1;
        for (int i=0; i<(int)colors.size(); ++i) {
            int t = sq(r-colors[i].r) + sq(g-colors[i].g) + sq(b-colors[i].b);
            if (t < mn) {
                mn = t;
                k = i;
            }
        }
        cout << colors[k].name << endl;
    }
    return 0;
}