How to add more variables inside of loops java

Question

Have each department's number of computers stored in variables. Have the program store the values in variables, calculate the total and average computers and display them.

example output: Chemistry: 4 Physics: 8 Music: 2 Math lab: 12

Total: 26 Average: 6.5

import java.util.Scanner;

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

    Scanner sc = new Scanner(System.in);

    System.out.print("What is the name of your first class?");
    String class1 = sc.nextLine();

    System.out.print("What is the name of your second class?");
    String class2 = sc.nextLine();

    System.out.print("What is the name of your third class?");
    String class3 = sc.nextLine();

    System.out.print("What is the name of your fourth class?");
    String class4 = sc.nextLine();

    System.out.print(" \n\n");
    System.out.println("How many computers are in each class?");
    System.out.print(class1 + ": \t");
    int class1comp = sc.nextInt();
    System.out.print(class2 + ": \t");
    int class2comp = sc.nextInt();
    System.out.print(class3 + ": \t");
    int class3comp = sc.nextInt();
    System.out.print(class4 + ": \t");
    int class4comp = sc.nextInt();
    int sum = class1comp + class2comp + class3comp + class4comp;
    double avg = sum / 4.0;

    System.out.print(" \n\n");

    System.out.println("\n\n" + class1 + ":\t" + class1comp);
    System.out.println(class2 + ":\t" + class2comp);
    System.out.println(class3 + ":\t" + class3comp);
    System.out.println(class4 + ":\t" + class4comp);

    System.out.println("\n");
    System.out.println("Total:\t\t" + sum);
    System.out.println("Average:\t" + avg);
  }
}

After unit 2: Allow the user to add more departments.

I want the user to be able to add more classes until they say stop. Then later ask how many computers each class needs. Then display them, add them to the sum and average.

You should try the public available and free tutorials at Oracle web site: https://docs.oracle.com/javase/tutorial/collections/ — Timothy Truckle, Sep 12 '18 at 13:00
@maio290 How would the person using the console be able to add infinite classes using arrays — Speedy Sapphire, Sep 12 '18 at 13:46
You could expand the array's size each time he enters a new input, but really, a List would be more suitable for this task. — maio290, Sep 12 '18 at 13:53

score 0 · Answer 1 · answered Sep 12 '18 at 14:12

This should work for your purposes , it uses an ArrayList for the class names and an array of integers for the grades. It uses the AddOrdinal method taken from this answer.

public static void main(String[] args) {
    Scanner scan = new Scanner(System.in);
    ArrayList<String> stringList = new ArrayList<>();
    String capture;
    int count =1;
    System.out.println("Please enter your "+AddOrdinal(count) +" class:");
    while (!((capture = scan.nextLine()).toLowerCase().equals("stop"))) {
        count++;
        stringList.add(capture);
        System.out.println("Please enter your "+AddOrdinal(count) +" class:");
    }
    System.out.println("How many computers are in each class?");
    int[] intList = new int[stringList.size()];
    for (int i = 0; i < stringList.size(); i++) {
        String className = stringList.get(i);
        System.out.println(className + "\t:");
        intList[i] = (scan.nextInt());
    }
    scan.close();
    Arrays.stream(intList).sum();
    int sum = Arrays.stream(intList).sum();
    double average = (double)sum/intList.length;
    /*
     Output goes here
    */
}

How to add more variables inside of loops java

1 Answers1