Прва

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.Random;
import java.util.Scanner;

class App implements Comparable<App>
{
    private final String name;
    private final String description;
    private final double price;
    private final int rating;

    public App(String n, String d, int r, double p)
    {
        name = n;
        description = d;
        price = p;
        rating = r;
    }

    public int compareTo(App rhs)
    {
        return (int)price - (int)rhs.price;
    }

    public String getName()
    {
        return name;
    }

    public String getDescription()
    {
        return description;
    }

    public double getPrice()
    {
        return price;
    }

    public int getRating()
    {
        return rating;
    }

    public static class NameComparator implements Comparator<App>
    {
        public int compare(App a1, App a2)
        {
            return a1.getName().compareTo(a2.getName());
        }
    }

    public static class DescriptionComparator implements Comparator<App>
    {
        public int compare(App a1, App a2)
        {
            return a1.getDescription().compareTo(a2.getDescription());
        }
    }

    class PriceComparator implements Comparator<App>
    {
        public int compare(App a1, App a2)
        {
            return new Double(a1.getPrice()).compareTo(new Double(a2.getPrice()));
        }
    }

    public static class RatingComparator implements Comparator<App>
    {
        public int compare(App a1, App a2)
        {
            return new Integer(a1.getRating()).compareTo(new Integer(a2.getRating()));
        }
    }
}

class AppManager
{
    private static int r;
    private ArrayList<App> AL;

    public AppManager(App... apps)
    {
        r = 0;
        AL = new ArrayList<App>();
        for(App app : apps)
        {
            AL.add(app);
        }
    }

    public App bestApp()
    {
        int best = 0;

        for(int i = 1 ; i < AL.size() ; ++i)
            if(AL.get(i).getRating() > AL.get(best).getRating())
                best = i;

        return AL.get(best);
    }

    public App cheapestApp()
    {
        int cheapest = 0;

        for(int i = 1 ; i < AL.size(); ++i)
        {
            if(AL.get(i).getPrice() < AL.get(cheapest).getPrice())
                cheapest = i;
        }

        return AL.get(cheapest);
    }




    public List<App> randomChoice()
    {
        List<App> result = new ArrayList<App>();

        //System.out.println(r);

        for(int i = 0 ; i < Math.min(3, AL.size()-r) ; ++i)
        {
            result.add(AL.get(r));
            r = (r+1) % AL.size();
        }

        return result;
    }

    public List<App> allApps(String attribute, boolean ascending)
    {
        List<App> AL2 = new ArrayList<App>(AL);
        if(attribute.equals("name"))
            Collections.sort(AL2,new App.NameComparator());
        else if(attribute.equals("price"))
            Collections.sort(AL2,new App.DescriptionComparator());
        else if(attribute.equals("rating"))
            Collections.sort(AL2,new App.RatingComparator());
        if(!ascending)
            Collections.reverse(AL2);
        return AL2;
    }

    public int[] ratingStats()
    {
        int[] result = new int[5];
        for(int i = 0 ; i < 5 ; ++i)
            result[i] = 0;

        for(int i = 0 ; i < AL.size() ; ++i)
            result[AL.get(i).getRating()-1]++;

        return result;
    }
}

public class AppManagerTest {
public static void main(String[] args) throws Exception {
        Scanner jin = new Scanner(System.in);
        int n = Integer.parseInt(jin.nextLine());
        App[] apps = new App[n];
        for ( int i = 0 ; i < n ; ++i ) {
            apps[i] = new App(jin.nextLine(),jin.nextLine(),jin.nextInt(),jin.nextDouble());
            jin.nextLine();
        }
        int k = jin.nextInt();
        AppManager am = new AppManager(apps);
        if ( k == 0 ) { //test everything but randomChoice
            while ( true ) {
                System.out.println();
                String cmd = jin.next();
                System.out.println(cmd);
                if ( cmd.equals("stop") ) break;
                if ( cmd.equals("bestApp") ) {
                    print(am.bestApp());
                }
                if ( cmd.equals("cheapestApp") ) {
                    print(am.cheapestApp());
                }
                if ( cmd.equals("allApps") ) {
                    print(am.allApps(jin.next(),jin.nextBoolean()));
                }
                if ( cmd.equals("ratingStats") ) {
                    System.out.println(Arrays.toString(am.ratingStats()));
                }
            }
        }
        else { //test randomChoice
            System.out.println("Testing random choice...");
            int w = jin.nextInt();
            for ( int q = 0 ; q < w ; ++q ) {
                boolean[] flags = new boolean[n];
                for ( int i = 0 ; i <= n/3 ; ++i ) {
                    List<App> res = am.randomChoice();
                    for ( App a : res ) {
                        int idx = idxOf(apps,a);
                        if ( idx == -1 ) System.out.println("You returned an app that wasn't in the list at all? What are you doing???");
                        if ( flags[idx] ) {
                            System.out.println("You returned an app twice, before returning all the apps in the list. I want to see all the apps first then you can give me duplicates.");
                            throw new Exception("App already returned");
                        }
                        flags[idx] = true;
                    }
                }
            }
            System.out.println("Great work on implementing randomChoice. That is just what we needed.");
        }
    }

    private static void print(App app) {
        System.out.println("Name: "+app.getName());
        System.out.println("Rating: "+app.getRating());
        System.out.printf("Price: %.2f$\n",app.getPrice());
    }

    private static void print(List<App> apps) {
        for ( App ap : apps ) {
            print(ap);
            System.out.println();
        }
    }

    private static int idxOf(App apps[],App a){
        for ( int i = 0 ; i < apps.length ; ++i )
            if ( equal(apps[i],a) ) return i;
        return -1;
    }

    private static boolean equal(App a , App b) {
        return a.getName().equals(b.getName())&&a.getPrice()==b.getPrice()&&a.getRating()==b.getRating();
    }

}