JF-Maps-Exercise-07.StudentAcademy

package com.company;

import java.util.*;

public class StudentAcademy {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        int n = Integer.parseInt(sc.nextLine());
        Map<String, List<Double>> students = new LinkedHashMap<>();

        for (int i = 0; i < n; i++) {
            String name = sc.nextLine();
            double grade = Double.parseDouble(sc.nextLine());

            students.putIfAbsent(name, new ArrayList<>());
            students.get(name).add(grade);

        }
        Map<String, Double> grades = new LinkedHashMap<>();

        for (Map.Entry<String, List<Double>> entry : students.entrySet()) {
            double avgGrade = entry.getValue().stream().mapToDouble(a->a).average().getAsDouble();

            if (avgGrade >= 4.5) {
                grades.put(entry.getKey(), avgGrade);
            }
        }

        grades.entrySet().stream().sorted((a,b) -> b.getValue().compareTo(a.getValue()))
                .forEach(student -> System.out.println(String.format("%s -> %.2f", student.getKey(), student.getValue())));

    }
}