package student;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.HashSet;
import java.util.Scanner;

import static java.lang.System.out;

public class Student implements Comparable<Student> {

    public final int id, score;

    public Student(int id, int score) {
        this.id = id;
        this.score = score;
    }

    @Override public String toString() {
        return id + "-" + score;
    }

    @Override public int compareTo(Student anotherStudent) {
        if (id != anotherStudent.id) {
            return compareAsc(id, anotherStudent.id);
        }
        if (score != anotherStudent.score) {
            return compareDsc(score, anotherStudent.score);
        }
        return 0;
    }

    private static int compareAsc(int a, int b) { return a < b ? -1 :  1; }
    private static int compareDsc(int a, int b) { return a < b ?  1 : -1; }

    @Override public int hashCode() {
        return id;
    }

    @Override public boolean equals(Object another) {
        return another instanceof Student && id == ((Student) another).id;
    }

    public static void main(String[] args) {
        List<Student> students = new ArrayList<>();
        Scanner scanner = new Scanner(System.in);
        scanner.useDelimiter("[-\\n]");
        while (scanner.hasNextInt()) {
            int id = scanner.nextInt();
            if (scanner.hasNextInt()) {
                int score = scanner.nextInt();
                students.add(new Student(id, score));
            }
        }

        Collections.sort(students);
        out.println(new HashSet(students));
    }
}