import java.util.*;
import java.io.*;

public class IndexPrestasiSiswa {
    public static void main(String[] args) {
        Scanner reader = new Scanner(System.in);
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));

        ArrayList<String> courses = new ArrayList<>();
        ArrayList<String> courseNames = new ArrayList<>();
        ArrayList<String> courseGrades = new ArrayList<>();
        ArrayList<Integer> universityCreditUnits = new ArrayList<>();

        Scanner courseReader = new Scanner(System.in);
        Scanner courseNameReader = new Scanner(System.in);
        Scanner courseGradeReader = new Scanner(System.in);
        Scanner universityCreditUnitReader = new Scanner(System.in);

        int results[] = new int[15];
        int menu;
        int coursesCount = 0;
        int gradeTotal = 0;
        int grade;
        int isExists = 0;
        double finalResult = 0;
        int universityCreditUnitsCount = 0;
        String choice = "Y";
        String courseCode;

        while (choice.equals("Y")) {
            System.out.print("\033[H\033[2J");
            System.out.println("Pendataan dan Perhitungan IPS (Indeks Prestasi Semester)");
            System.out.println("1.Pendataan Mata Kuliah");
            System.out.println("2.Perhitungan IPS");
            System.out.println("3.Update Grade");
            System.out.println("4.Keluar");
            System.out.print("Masukkan pilihan anda : ");

            menu = reader.nextInt();

            switch (menu) {
                case 1:
                    System.out.print("\033[H\033[2J");
                    System.out.print("Masukan jumlah mata kuliah : ");

                    coursesCount = reader.nextInt();

                    for (int x = 1; x <= coursesCount; x++) {
                        System.out.print("\033[H\033[2J");
                        System.out.print("Masukkan kode mata kuliah : ");
                        courses.add(courseReader.next());
                        System.out.print("Masukkan nama mata kuliah : ");
                        courseNames.add(courseNameReader.nextLine());
                        System.out.print("Masukkan grade mata kuliah : ");
                        courseGrades.add(courseGradeReader.next());
                        System.out.print("Masukkan jumlah SKS : ");
                        universityCreditUnits.add(universityCreditUnitReader.nextInt());
                    }
                    break;
                case 2:
                    System.out.print("\033[H\033[2J");
                    System.out.println("");
                    System.out.println("Matakuliah yang anda ambil adalah : ");
                    System.out.printf("%-9s %10s %20s %10s\n","Kode","Matkul","grade","SKS");

                    for (int x = 0; x < coursesCount; x++) {
                        System.out.printf("%-14s", courses.get(x));
                        System.out.printf("%-23s", courseNames.get(x));
                        System.out.printf("%-13s", courseGrades.get(x));
                        System.out.printf("%-10s", universityCreditUnits.get(x));
                        System.out.println("");

                        switch (courseGrades.get(x)) {
                            case "A":
                                grade = 4;
                                break;
                            case "B":
                                grade = 3;
                                break;
                            case "C":
                                grade = 2;
                                break;
                            case "D":
                                grade = 1;
                                break;
                            default:
                                grade = 0;
                                break;
                        }

                        results[x] = grade * universityCreditUnits.get(x);
                        gradeTotal = gradeTotal + results[x];
                        universityCreditUnitsCount = universityCreditUnitsCount + universityCreditUnits.get(x);
                    }

                    finalResult = gradeTotal / universityCreditUnitsCount;
                    System.out.println("Nilai IPS Anda adalah : " + finalResult);
                    break;
                case 3:
                    System.out.print("\033[H\033[2J");
                    System.out.print("Masukkan kode mata kuliah : ");
                    courseCode = reader.next();

                    for (int x = 0; x < coursesCount; x++) {
                        if (courses.get(x).equals(courseCode)) {
                            isExists = 1;
                            System.out.print("Masukkan grade baru : ");
                            courseCode = reader.next();
                            System.out.printf("%-9s %10s %20s %10s\n","Kode","Matkul","grade","SKS");
                            courseGrades.set(x, courseCode);

                            for (int a = 0; a < coursesCount; a++) {
                                System.out.printf("%-14s", courses.get(a));
                                System.out.printf("%-23s", courses.get(a));
                                System.out.printf("%-13s", courseGrades.get(a));
                                System.out.printf("%-10s", universityCreditUnits.get(a));
                                System.out.println("");
                            }
                            System.out.println("");
                        }
                    }

                    if (isExists != 1) {
                        System.out.println("Kode mata kuliah yang anda input tidak tersedia!");
                        System.out.println("");
                    }
                    break;
                case 4:
                    System.exit(0);
                    break;

                default:
                    System.out.println("Menu tidak tersedia!");
                    break;
            }

            System.out.print("Kembali ke menu utama? (Y/T) : ");

            try {
                choice = bufferedReader.readLine();
            } catch (IOException e) {

            }
        }
    }
}