import java.util.List;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Map;

import java.util.Scanner;

class Student {

    String firstName;

    String lastName;

    String ID_No;

    double CGPA;

    String Department;

    String ContactNo;

    List<String> Courses;

    Map <String, Integer> CourseMark;

    

    public Student( String firstName,

     String lastName,

    String ID_No,

    double CGPA,

    String Department,

    String ContactNo)

    {

        this.firstName = firstName;

        this.lastName = lastName;

        this.ID_No = ID_No;

        this.CGPA = CGPA;

        this.Department = Department;

        this.ContactNo = ContactNo;

         this.Courses = new ArrayList<>();

         this.CourseMark = new HashMap<>();

    }

}

public class StudentErpSyestem{

    private  static List<Student> students = new ArrayList<>();

    public static void main(String args[]){

        Scanner sc = new Scanner(System.in);

        while(true){

          

            System.out.println("1. Add student details:  ");

            System.out.println("2.Find student by roll number: ");

            System.out.println("3.Exit: ");

            System.out.println("Select an option: ");

            int choice = sc.nextInt();

            sc.nextLine();

            switch(choice){

             

                case 1: 

                   System.out.println("Case 1.... ");           //  add students details

                   break;

                case 2: 

                   System.out.println("Case 2.... ");           // find student roll number

                   break;

                case 3: 

                   System.out.println("Case 3.... ");

                   break;

                case 4: 

                   System.out.println("Exiting.... ");

                   System.exit(0);

                   break;

                default:

                   System.out.println("Invalid choice. Please select a valid option!");

            }

        }

        // Student Tanveer = new Student("Tanveer", "Islam", "21300029", 3.89, "CSE","01978653421");

        // System.out.println(Tanveer.CGPA);

        //  Student Emon = new Student("Emon", "Dhali","2130079",3.50,"CSE","01908707136");

        //  System.out.println(Emon.firstName);

        //  System.out.println(Emon.lastName);

        //  System.out.println(Emon.Department);

       

    }

}