/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package ppa2_cv_04_2_a14b0537p;

import java.util.Arrays;
import java.util.Scanner;

/**
 *
 * @author Milan
 */
public class PPA2_cv_04_2_A14B0537P
{
    public static    char k = 'k';
    public static    char p = 'p';
    public static    char o = 'o';
    public static    char prvni = 'A';
    public static    char[] fronta = new char[3];
    public static    int zacatekSeznamu = 0;
    public static    int konecSeznamu = 0 ;
    public static    int pocetVeFronte = 0;
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);

        for(int i = 0; true;i++)
        {
            String vstup = sc.nextLine();
            if(vstup.charAt(0)== p)
            {

                fronta[konecSeznamu] = (prvni);
                prvni++;
                konecSeznamu++;
                pocetVeFronte++;
                zmenaPole();


                vypsaniPole();

            }
            if(vstup.charAt(0)== o)
            {
                if(zacatekSeznamu != konecSeznamu)
                {
                    zacatekSeznamu++;
                    pocetVeFronte--;
                    posoupnuti();
                    zmenaPole();
                    vypsaniPole();

                } else
                {
                    break;
                }
            }
            if(zacatekSeznamu==konecSeznamu)
            {
                System.out.println("Fronta je prazdna");
                if(sc.nextLine().charAt(0)==o)
                {
                    System.out.println("Chyba, fronta je prazdna");

                }
            }

            if(vstup.charAt(0)== k)
            {
                if(zacatekSeznamu!=konecSeznamu)
                {
                    System.out.println("Ve fronte nekdo zbyl");
                }
                break;
            }

            }

        }


    public static void zmenaPole()

    {

        if(pocetVeFronte >= fronta.length )
        {
            char[] tempFronta = new char[fronta.length * 2];
            System.arraycopy(fronta, 0, tempFronta, 0, fronta.length);
            fronta=tempFronta;
        }
        if(pocetVeFronte <= 2 * (fronta.length) && pocetVeFronte >= 3   )
        {
            int novadylka = fronta.length/2 ;
            char[] tempFronta = new char[novadylka];
            System.arraycopy(fronta, 0, tempFronta, 0, tempFronta.length); // tady dodelat
            fronta=tempFronta;
        }

    }
    public static void vypsaniPole()
    {
        String soucasnaFronta="";
        for(int i = zacatekSeznamu; i<fronta.length;i++)
        {
            soucasnaFronta += fronta[i];
        }
        System.out.println(soucasnaFronta);
    }

    public static void posoupnuti()
    {
        char[] tempFronta = new char[fronta.length];
        System.arraycopy(fronta, 1, tempFronta, 1, fronta.length - 1);
        fronta = tempFronta;
    }
}