Average Students Grades

package SetsAndMaps3;

import java.util.*;

public class AverageStudentsGrades {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        Map<String, List<Double>> students = new TreeMap<>();

        int num = Integer.parseInt(scanner.nextLine());

        for (int index = 0; index < num; index++) {
            String[] input = scanner.nextLine().split("\\s+");

            String name = input[0];
            double grade = Double.parseDouble(input[1]);
            students.putIfAbsent(name, new ArrayList<>());
            students.get(name).add(grade);
        }

        for (Map.Entry<String, List<Double>> entry : students.entrySet()) {

            System.out.print(entry.getKey() + " -> ");

            double average = 0;
            for (Double s : entry.getValue()) {
                System.out.printf("%.2f ", s);
                average += s;
            }
            System.out.printf("(avg: %.2f)%n", average / entry.getValue().size());
        }
    }
}