import java.util.Scanner;

public class Main{
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String str="yukicoder";
		while(sc.hasNext()){
			int n=sc.nextInt();
			if(n==0) break;
			System.out.println(str.charAt(n-1));
		}
	}
}