averageagemodified

import java.util.Scanner;

public class AverageAgeModified {

	public static void main(String[] args) {

		// Add scanner so we can get user input
		Scanner scan = new Scanner(System.in);

		int total = 0;
		int counter = 0;
		int ages = 0;
		
		System.out.print("Enter number of ages: ");
		ages = scan.nextInt();
		
		while (counter < ages) {
			System.out.print("Enter age: ");
			total += scan.nextInt();
			counter++;
		}
		
		scan.close();

		double average = total / (double) ages;

		System.out.println("Average age is " + average);
	}

}

bookorderforloop

import java.util.Scanner;

public class BookOrderForLoop {
	
	private static double subtotal = 0;

	public static void main(String[] args) {
		
		Scanner scan = new Scanner(System.in);
		
		System.out.print("Enter number of books: ");
		int numberofbooks = scan.nextInt();
		
		for (int i = 0; i < numberofbooks; i++) {
			System.out.print("Enter book " + (i+1) + "'s cost: ");
			subtotal += scan.nextDouble();
		}
				
		scan.close();
		
		final double tax = 6.5;
		final double shipping_charge = 2.95;
		
		double totalTax = tax * subtotal / 100;
		double totalshipping = shipping_charge * numberofbooks;
		double ordertotal = subtotal + totalTax + totalshipping;
		
		System.out.printf("Number of books: %d\n", numberofbooks);
		System.out.printf("Book subtotal: %.2f\n", subtotal);
		System.out.printf("Tax: %.2f\n", totalTax);
		System.out.printf("Shipping: %.2f\n", totalshipping);
		System.out.printf("Order total: %.2f\n", ordertotal);
	}

}

bookordersentinal

import java.util.Scanner;

public class BookOrderSentinal {
	
	private static double subtotal = 0;
	private static int numberofbooks = 0;

	public static void main(String[] args) {
		
		Scanner scan = new Scanner(System.in);
		double cost = 0;
		
		do {
			System.out.print("Enter book " + (numberofbooks+1) + "'s cost (or -1 to quit): ");
			cost = scan.nextDouble();
			if (cost != -1) {
				numberofbooks++;
				subtotal += cost;
			}
		} while (cost != -1);
		scan.close();
		
		final double tax = 6.5;
		final double shipping_charge = 2.95;
		
		double totalTax = tax * subtotal / 100;
		double totalshipping = shipping_charge * numberofbooks;
		double ordertotal = subtotal + totalTax + totalshipping;
		
		System.out.printf("Number of books: %d\n", numberofbooks);
		System.out.printf("Book subtotal: %.2f\n", subtotal);
		System.out.printf("Tax: %.2f\n", totalTax);
		System.out.printf("Shipping: %.2f\n", totalshipping);
		System.out.printf("Order total: %.2f\n", ordertotal);
	}

}

printstars

import java.util.Scanner;

public class PrintStarts {

	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		String stars = "***********";
		int counter = 0;
		
		System.out.print("Enter number of rows: ");
		int x = scan.nextInt();
		scan.close();
		
		do {
			System.out.println(stars);
			counter++;
		} while (counter < x);
	}

}

ticketcounter

import java.util.Scanner;

public class TicketCounter {
	
	private static int ticketsAvailable = 75;
	private static int counter = 0;
	private static final int MAX_TICKETS_PER_CUSTOMER = 6;

	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		while(ticketsAvailable > 0) {
			System.out.print("Enter number of tickets: ");
			int tickets = scan.nextInt();
			if (tickets > 0 && tickets <= MAX_TICKETS_PER_CUSTOMER && ticketsAvailable >= tickets) {
				ticketsAvailable -= tickets;
				counter++;
			} else {
				System.out.println("Incorrect input. Try again.");
			}
		}
		scan.close();
		System.out.println(counter);
		
	}

}