// by KR zaklucenia [zak] c
#include <iostream>
#include <vector>
#include <string>
using namespace std;
int main()
{
	double n;
	string ciag, wynik;
	cin >> n >> ciag;
	int one = 0, dl = n;
	for (int i = 0; i < 8 * n; i++)
	{
		if (ciag[i] == '1')
		{
			one++;
		}
	}
	while (one / n > 5)
	{
		wynik+="o";
		one -= 6; n--;
	}
	while (one / n > 4)
	{
		wynik += "g";
		one -= 5; n--;
	}
	while (one / n > 3)
	{
		wynik += "c";
		one -= 4; n--;
	}
	while (one / n > 2)
	{
		wynik += "a";
		one -= 3; n--;
	}
	if (wynik.length() != dl)
	{
		cout << "NIE";
		return 0;
	}
	cout << wynik;
	return 0;
}