public class Change2
{
    public static void main(String[] args)
    {
        // Get the price and payment.
        int price = getPrice();
        int payment = getPayment();

        // Now make sure they paid enough for the sale, and that the sale 
        // amount is a positive number.
        if (!validInput(price,payment))
        {    
            // If we made it here then the user gave us bad input.  
            // Print a message and exit the program.
            System.out.println("Invalid input.  Please try again.");
            return;
        }

        // If we made it here then we have valid input.  

        // Calculate the amount of change to give.
        int change = payment - price;
        
        // Now get the number of quarters to return .
        int quarters = getNumCoins(25,change);

        // Compute remaining change to give.
        int remainder = change % 25;

        // Now get the number of dimes.
        int dimes = getNumCoins(10,remainder);
    
        // Compute remaining change to give.
        remainder = remainder % 10;

        // Get the number of nickels.
        int nickels = getNumCoins(5,remainder);
    
        // Compute remaining change to give.
        remainder = remainder % 5;

        // The remaining change to give must be given in pennies.
        int pennies = remainder;

        // Print the results.
        printResults(quarters, dimes, nickels, pennies, change);
    }
    
    public static int getPrice()
    {
        // Declare a TextInput Object.
        TextInput tin = new TextInput();

        // Prompt the user to enter the price.
        System.out.print("What is the price? ");

        // Read and return the price from the keyboard.
        return tin.readInt();
    }	
    
    public static int getPayment()
    {
        // Declare a TextInput Object.
        TextInput tin = new TextInput();

        // Prompt the user to enter the payment.
        System.out.print("What is the payment? ");

        // Read and return the payment from the keyboard.
        return tin.readInt();
    }

    public static boolean validInput(int price, int payment)
    {
        if (price < 1)
        {
            // We don't give items away so price must be at least 1
            return false;
        }

        // If we made it here then the price must be valid. 
        // Now make sure that the payment is at least as high
        // as the price.
        if (payment < price)
        {
            return false;
        }

        // If we made it here then the input must be valid
        return true;
    }

    public static int getNumCoins(int value, int changeLeft)
    {
        return changeLeft / value;
    }

    public static void printResults(int quarters, int dimes, int nickels, int pennies, int change)
    {
        System.out.println("Quarters: " + quarters);
        System.out.println("   Dimes: " + dimes);
        System.out.println(" Nickels: " + nickels);
        System.out.println(" Pennies: " + pennies);
        System.out.println("Total change: " + change);
    }
}