02. Exam Preparation

import java.util.Scanner;

public class ExamPreparation {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int badGrades = Integer.parseInt(scanner.nextLine());
        String task = "", lastProblem = "";
        int badGradesCounter = 0, tasksCount = 0;
        double sumGrades = 0, grade = 0;

        while (!(task = scanner.nextLine()).equals("Enough")) {
            grade = Double.parseDouble(scanner.nextLine());
            sumGrades += grade;
            tasksCount++;

            if (grade <= 4) {
                badGradesCounter++;

                if (badGradesCounter == badGrades) {
                    System.out.printf("You need a break, %d poor grades.\n", badGrades);
                    break;
                }
            }

            lastProblem = task;
        }

        if (task.equals("Enough")) {
            System.out.printf("Average score: %.2f\n", sumGrades / tasksCount);
            System.out.printf("Number of problems: %d\n", tasksCount);
            System.out.printf("Last problem: %s\n", lastProblem);
        }
    }
}

ИЛИ:

import java.util.Scanner;

public class ExamPreparation {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int badGrades = Integer.parseInt(scanner.nextLine());
        String task = "", lastProblem = "";
        int badGradesCounter = 0, tasksCount = 0;
        double sumGrades = 0, grade = 0;

        while (badGradesCounter != badGrades
                &&!(task = scanner.nextLine()).equals("Enough")) {
            grade = Double.parseDouble(scanner.nextLine());
            if (grade <= 4) {
                badGradesCounter++;
            }
            sumGrades += grade;
            lastProblem = task;
            tasksCount++;
        }

        if (badGradesCounter == badGrades) {
            System.out.printf("You need a break, %d poor grades.\n", badGrades);
        } else {
            System.out.printf("Average score: %.2f\n", sumGrades / tasksCount);
            System.out.printf("Number of problems: %d\n", tasksCount);
            System.out.printf("Last problem: %s\n", lastProblem);
        }
    }
}