Ex04, 19.16.2021

import java.util.Scanner;

public class Ex04 {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int y; // grade entered by the user
        int c = 0; // count valid grades
        int sum = 0;
        double avg;

        // get first grade
        System.out.print("Enter your grade (0 to 100): ");
        y = in.nextInt();

        while (y >= 0 && y <= 100) {
            // valid grade
            c++; // add 1 to the counter
            sum = sum + y; // add grade to sum

            // get next grade
            System.out.print("Enter your grade (0 to 100): ");
            y = in.nextInt();
        }

        System.out.println("You have " + c + " grades");
        System.out.println("The sum of grades is " + sum);
        avg = (double) sum / c;
        System.out.println("The average is " + avg);
        in.close();
    }
}