如何计算硬币数量？

Question

Hi I'm learning Java and am producing code that converts the number of pennies entered in to change.

So if I enter 439p it prints: 439p 2*200p 4*100p 1*20p 1*10p 1*5p 4*1p. The last thing I need to implement is including how many coins there are in total in the print statement

So in this case it should print as: 439p 13 coins 2*200p 4*100p 1*20p 1*10p 1*5p 4*1p. I know it's probably simple but I'm really not sure how to do this so any guidance would be appreciated :)

My code is

class Main { 
public static void main( String args[] ) {

    System.out.print("#Please enter the amount of change : ");
    int change = BIO.getInt();

    while(change > 0)
    {
        int twopounds, pounds, fifty, twenty, ten, five, two, one;

        twopounds = change / 200;
        int left = change % 200;

        pounds = change / 100;
        left = change % 100;

        fifty = left / 50;
        left = left % 50;

        twenty = left / 20;
        left = left % 20;

        ten = left / 10;
        left = left % 10;

        five = left / 5;
        left = left % 5;

        two = left / 2;
        two = left % 2;

        one = left / 1; 

        if (change == 1)
        {
            System.out.print("1 coin");
        }

        if (change > 500)
        { 
            System.out.print("Invalid amount " + change + "p" + "\n");
        }

        if (change <= 500 && change > 1)

            System.out.print(change + "p ");
        {
            if ( twopounds > 0 )
            {
                System.out.print( twopounds > 0 ? twopounds + "*200p " : "" );
            }

            if ( pounds > 0 )
            {
                System.out.print( pounds > 0 ? pounds + "*100p " : "" );
            }

            if ( fifty > 0 )
            {
                System.out.print( fifty > 0 ? fifty + "*50p " : "" );
            }

            if ( twenty > 0 )
            {
                System.out.print( twenty > 0 ? twenty + "*20p " : "" );
            }

            if ( ten > 0 )
            {
                System.out.print( ten > 0 ? ten + "*10p " : "" );
            }

            if ( five > 0 )
            {
                System.out.print( five > 0 ? five + "*5p " : "" );
            }

            if ( two > 0 )
            {
                System.out.print( two > 0 ? two + "*2p " : "" );
            }

            if ( one > 0 )
            {
                System.out.print( one > 0 ? one + "*1p " : "" );
            }
        }
        System.out.print("#Please enter the amount of change : ");
        change = BIO.getInt();
    }

}

Answer 1

简单如：

int nbCoins = twopounds + pounds + fifty + twenty + ten + five + two + one

Answer 2

The statement

pounds = change / 100;
left = change % 100;

should be

pounds = left / 100;
left = left % 100;

Answer 3

Also, in addition to unxnut's remark, you could shorten your code a little bit if you replace the

if ( x > 0 ) {
     System.out.print( x > 0 ? x + "*...p " : "" );
}

statements with either

System.out.print( x > 0 ? x + "*...p " : "" );

or

if ( x > 0 ) {
    System.out.print(x + "*...p ");
}

Either of those conditions will be sufficient for a conditional output of the parts that make up the change.