Question

I have to write a Java program that tells what coins to give out for any amount of change from 1 cent to 99 cents. For example, if the amount is 86 cents, the output would be something like the following:

86 cents can be given as 3 quarters, 1 dime and 1 penny.

Use coin denominations of 25, 10, 5, and 1. Your program will use the following method(among others):

public static int computeCoin(int coinValue,);
// Precondition: 0 < coinValue < 100; 
// Postcondition: returned value has been set equal to the maximum 
//number of coins of the denomination coinValue cents that can be 
//obtained from amount (a different variable) cents. amount has been 
//decreased by the value of the coins, that is, decreased by     
//returnedValue*coinValue.

So far this is what I have but I think I am missing more can somebody give me a hand?
And I am also not suppose to use doubles instead int.

public class Assignment6{
   public static void main(String [] args){
   amount = (int)(Double.parseDouble(args[0])*100);

   System.out.println("Five: " + computeCoin(500));
   System.out.println("one: " + computeCoin(100) );
   System.out.println("Q : " + computeCoin(25) );
   System.out.println("D : " + computeCoin(10) );
   System.out.println("N : " + computeCoin(5) );
   System.out.println("P : " + computeCoin(1) );
}

Answer 1

public class Assignment6 {
    private static int amount = 0;
    public static void main(String[] args) {
        amount = (int)(Double.parseDouble(args[0])*100);
        System.out.println("Five: " + computeCoin(500));
        System.out.println("one: " + computeCoin(100) );
        System.out.println("Q : " + computeCoin(25) );
        System.out.println("D : " + computeCoin(10) );
        System.out.println("N : " + computeCoin(5) );
        System.out.println("P : " + computeCoin(1) );
    }

    public static int computeCoin(int cointValue) {
        int val = amount / cointValue;
        amount -= val * cointValue;
        return val;
    }
}

The trick here lies in the computeCoin method, and in the fact that the division is integer division, so val will hold the ‘maximum’ number of coins of the given value (coinValue) whose total value does not exceed amount.