Receive average scores and check the number of scores in a range | Java

Question

Write a java program that reads the grades of 10 students, which is from 1 to 100, from the entrance, specifying that the scores of some people are from 90 to 100, some people are from 60 to 89 and some people are from 1 to 59. The program should print the average scores at the end. This is code for average, how can i add else and if or while to review how much numbers are in range 1 to 59 or 60 to 89 or 90 to 100?

import java.util.Scanner;

public class EhsanNp {

    public EhsanNp() {
        String getStr = getUserNums();
        double result = userAvg(getStr);
        printAverage(result, getStr);

    }

    public String getUserNums() {
        Scanner in = new Scanner(System.in);
        System.out.println("Please enter ten numbers separated by spaces: ");
        return in.nextLine();
    }

    public static double userAvg(String str) {
        String[] arr = str.split(" ");
        double sum = 0.0;
        double average = 0.0;
        for (int i = 0; i < arr.length; i++) {
            sum += Integer.parseInt(arr[i]);
        }
        if (arr.length > 0) {
            average = sum / arr.length;
        }

        return average; // how do I get the program to count what to divide by since user can input 5- 10?
    }

    public static void printAverage(double average, String userNumInput) {
        System.out.printf("The average of the numbers " + userNumInput + "is %.2f", average);

    }

    public static void main(String[] args) {
        new EhsanNp();

    }
}

Answer 1

You can simply add three variables which store the number of grades between 1 to 59, 60 to 89 and 90 to 100 and increment them in the for loop. For example:

import java.util.Scanner;

public class EhsanNp {

    int lowGrades;
    int middleGrades;
    int highGrades;

    public EhsanNp() {
        lowGrades = 0;
        middleGrades = 0;
        highGrades = 0;
        String getStr = getUserNums();
        double result = userAvg(getStr);
        printAverage(result, getStr);
        
    }

    public String getUserNums() {
        Scanner in = new Scanner(System.in);
        System.out.println("Please enter ten numbers separated by spaces: ");
        return in.nextLine();
    }

    public static double userAvg(String str) {
        String[] arr = str.split(" ");
        double sum = 0.0;
        double average = 0.0;
        for (int i = 0; i < arr.length; i++) {
            sum += Integer.parseInt(arr[i]);
            if (Integer.parseInt(arr[i]) >= 1 && Integer.parseInt(arr[i]) <= 59) {
                lowGrades++;
            }
            else if (Integer.parseInt(arr[i]) >= 60 && Integer.parseInt(arr[i]) <= 89) {
                middleGrades++;
            }
            else {
                highGrades++;
            }
        }
        if (arr.length > 0) {
            average = sum / arr.length;
        }

        return average; // how do I get the program to count what to divide by since user can input 5- 10?
    }

    public static void printAverage(double average, String userNumInput) {
        System.out.printf("The average of the numbers " + userNumInput + "is %.2f", average);

    }

    public static void main(String[] args) {
        new EhsanNp();

    }
}

Then you can do whatever you want with the variables like displaying them for example.