import java.util.*;

public class Main {
    public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		String sample = "yukicoder";
		String str = scan.nextLine();
	
		for (int i = 0; i < str.length(); i++) {
			if (str.charAt(i) == '?') {
				System.out.println(sample.charAt(i));
				break;
			}
		}
    }
}