import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner indata = new Scanner(System.in);
        int n = indata.nextInt();
        int[] arr = new int[n];
        for (int i = 0; i < n; i++) {
            arr[i] = indata.nextInt();
        }
        Arrays.sort(arr);
        for (int i = 1; i < n; i++) {
            if (arr[i] == arr[i-1]) {
                System.out.println("YES");
                return;
            }
        }
        
        System.out.println("NO");
    }
}

import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner indata = new Scanner(System.in);
        int n = indata.nextInt();
        Set<Integer> set = new HashSet<>();
        StringBuilder out = new StringBuilder();
        for (int i = 0; i < n; i++) {
            int z = indata.nextInt();
            if (!set.contains(z)) {
                set.add(z);
                 out.append(z).append(" ");
                }
            }
        out.setLength(out.length()-1);
        System.out.println(out);
        }
    
}

import java.util.*;
public class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
       
        String sid1 = sc.next();
        String name1 = sc.next();
        int age1 = sc.nextInt();
        String major1 = sc.next();
        Student student1 = new Student();
        student1.setSid(sid1);
        student1.setName(name1);
        student1.setAge(age1);
        student1.setMajor(major1);

        String sid2 = sc.next();
        String name2 = sc.next();
        int age2 = sc.nextInt();
        String major2 = sc.next();
        Student student2 = new Student(sid2, name2, age2, major2);
        student1.print();
        student2.print();
    }
}
class Student{
    private String sid;
    private String name;
    private int age;
    private String major;
    public String getSid(){
        return sid;
    }
    public void setSid(String sid){
        this.sid = sid;
    }
    public String getName(){
        return name;
    }
    public void setName(String name){
        this.name = name;
    }
    public int getAge(){
        return age;
    }
    public void setAge(int age){
        if(age > 0)
            this.age = age;
        else 
            this.age = 0;
    }
    public String getMajor(){
        return major;
    }
    public void setMajor(String major){
        this.major = major;
    }
    public Student(){}
    public Student(String sid, String name,int age,String major)
{
        this.sid = sid;
        this.name = name;
        if(age>0)
            this.age = age;
        else
            this.age = 0;
        this.major = major;
}
    public void print()
    {
        System.out.println("学号："+sid+"，姓名："+name+"，年龄："+age+"，专业："+major);
    }
    
 }

import java.util.*;
import java.text.DecimalFormat;
public class Main{
    public static void main(String[]args){
    DecimalFormat f = new DecimalFormat("#.000000");
    Scanner indata = new Scanner(System.in);
    int dushu = indata.nextInt();
    int fengshu =indata.nextInt();
    double miaoshu =indata.nextDouble();
    System.out.print(dushu + "°" + fengshu + "′" + miaoshu + "″" + " = " + f.format((double)(dushu + (double)fengshu/60+miaoshu/3600)));
    }
    
}

import java.util.*;
class Dish {
    String name;
    int unit_price;

    Dish(String name, int unit_price) {
        this.name = name;
        this.unit_price = unit_price;
    }

    int getPrice(int portion) {
        double p = 0;
        if (portion == 1) {
            p = unit_price;
        }
        if (portion == 2) {
            p = unit_price * 1.5;
        }
        if (portion == 3) {
            p = unit_price * 2;
        }
       return (int) Math.round(p);
    }
}

class Menu {
    Dish[] dishes;

    Dish searchDish(String dishName) {
        for (Dish dish : dishes) {
            if (dish.name.equals(dishName)) {
                return dish;
            }
        }
        return null;
    }
}

class Record {
    Dish dish;
    int portion;

    int getPrice() {
        return dish.getPrice(portion);
    }
}

class Order {
    Record[] records;

int getTotalPrice() {
        Record[] nonNullRecords = Arrays.copyOf(records, records.length);
        int totalPrice = 0;
        for (Record record : nonNullRecords) {
            if (record != null) {
                totalPrice += record.getPrice();
            }
        }
        return totalPrice;
    }

    Record addARecord(String dishName, int portion, Menu menu) {
        Dish dish = menu.searchDish(dishName);
        if (dish == null) {
            System.out.println(dishName + " does not exist");
            return null;
        }
        Record record = new Record();
        record.dish = dish;
        record.portion = portion;
        return record;
    }
}

public class Main {
    public static void main(String[] args) {
        Menu menu = new Menu();
        menu.dishes = new Dish[4];
        menu.dishes[0] = new Dish("西红柿炒蛋", 15);
        menu.dishes[1] = new Dish("清炒土豆丝", 12);
        menu.dishes[2] = new Dish("麻婆豆腐", 12);
        menu.dishes[3] = new Dish("油淋生菜", 9);
        Order order = new Order();
        order.records = new Record[10];
        Scanner indata = new Scanner(System.in);
        int i = 0;
        while (true) {
            String input = indata.next();
            if (input.equals("end")) {
                break;
            }
            String dishName = input;
            int portion = Integer.parseInt(indata.next());
            Record record = order.addARecord(dishName, portion, menu);
            if (record != null) {
                order.records[i] = record;
                i++;
            }
        }
        int totalPrice = order.getTotalPrice();
        System.out.println(totalPrice);
    }
}

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String dateString1 = scanner.nextLine();
        if (!isValidDate(dateString1)) {
            System.out.println(dateString1 + "无效!");
        if(!scanner.hasNext())
            return;
        }
        String dateString2 = scanner.next();
        String dateString3 = scanner.next();
        if (!isValidDate(dateString2)||!isValidDate(dateString3)) {
            System.out.print(dateString2 + "或" + dateString3 + "中有不合法的日期.");
            return;
        }
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
        Date date1;
        try {
            date1 = dateFormat.parse(dateString1);
        } catch (ParseException e) {
            return;
        }
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date1);
        int year = calendar.get(Calendar.YEAR);
        boolean isLeapYear = isLeapYear(year);
        if (isLeapYear) {
            System.out.println(dateString1 + "是闰年.");
        } 
        int dayOfYear = calendar.get(Calendar.DAY_OF_YEAR);
        int dayOfMonth = calendar.get(Calendar.DAY_OF_MONTH);
        int dayOfWeek = calendar.get(Calendar.DAY_OF_WEEK)-1;
        if(dayOfWeek==0){
            System.out.println(dateString1 + "是当年第" + dayOfYear + "天,"+ "当月第" + dayOfMonth + "天,"+"当周第7天.");
        }else
        {System.out.println(dateString1 + "是当年第" + dayOfYear + "天,"+ "当月第" + dayOfMonth + "天,"+"当周第" + dayOfWeek + "天.");
        }
        Date date2, date3;
        try {
            date2 = dateFormat.parse(dateString2);
            date3 = dateFormat.parse(dateString3);
        } catch (ParseException e) {
            return;
        }
        if (date3.before(date2)) {
            System.out.println(dateString3 + "早于" + dateString2 + ",不合法!");
            return;
        }
        long diff = date3.getTime() - date2.getTime();
        long diffDays = diff / (24 * 60 * 60 * 1000);
        long diffMonths = date3.getMonth() - date2.getMonth();
        long diffYears = date3.getYear() - date2.getYear();

System.out.println(dateString3+"与"+dateString2+"之间相差"+diffDays+"天,"+"所在月份相差"+diffMonths+",所在年份相差"+diffYears+".");
    }

    public static boolean isValidDate(String dateString) {
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
        dateFormat.setLenient(false);
        try {
            dateFormat.parse(dateString);
            return true;
        } catch (ParseException e) {
            return false;
        }
    }

    public static boolean isLeapYear(int year) {
        if (year % 400 == 0) {
            return true;
        } else if (year % 100 == 0) {
            return false;
        } else if (year % 4 == 0) {
            return true;
        } else {
            return false;
        }
    }
}