Link to home
Start Free TrialLog in
Avatar of rgill67
rgill67

asked on

making change using int and mod division

I am writing a program that calculates change returned, but I need to do so with both int and mod division.  Here are the problems I am having:
1.  Once I do int division, how do I do mod division?
2.  I want to use a switch, but the compiler won't let use a double as a value in my case, so what value could I use??

here is my code:

amtChange=price-paid;
switch(amtChange)
case 10.00:  tens=(amtChange/10.00)+.005;
      amtChange=amtChange-(10.00*tens);

case 1.00: dollars = (amtChange / 1.00)+.005;      
        amtChange = amtChange - (1.00*dollars);

case .25:  quarters = (amtChange / .25)+.005;
        amtChange = amtChange - (.25 * quarters);

case .10:  dimes = (amtChange / .10)+.005;
          amtChange = amtChange - (.10 * dimes);

case .05:  nickels = (amtChange / .05)+.005;
         amtChange = amtChange - (.05 * nickels);  

default:  pennies = (amtChange / .01)+.005;

Thanks...
ASKER CERTIFIED SOLUTION
Avatar of tinchos
tinchos

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Avatar of n_fortynine
n_fortynine

using both: For example: change is 24.38
multiply that by 100 gives you 2438.
2438%1000 gives 2, so 2 $10
438%100 gives 4 so 4 $1
38/25 gives 1 so 1 quarter
13/5 gives 2 so 2 nickles
3/1 gives 3 so 3 pennies.

With the switch statement you're using I guess you can do switch(atmChange*100)
case 1000:
case 100:
case 25:
etc.

Is that what you want?
sorry tinchos, i was writing while you posted :)
Ok, no problem

happens all the time

:)
rgill67,
> I am writing a program that calculates change returned, but I need to do so
> with both int and mod division.  Here are the problems I am having:
> 1.  Once I do int division, how do I do mod division?
> 2.  I want to use a switch, but the compiler won't let use a double as a value
> in my case, so what value could I use??

There is no need for a switch.  A switch is for when you want to process one of a different number of values.  For this, you need to process EACH value (10's, then 1's, then quarters, etc.).  You don't just want to do one.

So, try this:
      amtChange = price-paid;

      tens = amtChange / 10.00;
      amtChange = fmod( amtChange, 10.00 );

      dollars = amtChange;
      amtChange = fmod( amtChange, 1.00 );

      quarters = amtChange / 0.25;
      amtChange = fmod( amtChange, 0.25 );

      dimes = amtChange / 0.10;
      amtChange = fmod( amtChange, 0.10 );

      nickels = amtChange / 0.05;
      amtChange = fmod( amtChange, 0.05 );

      pennies = amtChange / 0.01;

I assumed that amtChange and price-paid are floats or doubles.  If they are not, then this will need to be tweaked slightly, but I can help you with that.


Hope that helps,
Dex*
rgill67,
first of all i think there is no need to use switch case over here.
I think you are dividing the variable with it self only
i.e. when amtChange is 10
then you are doing amChange/10
which obvious means 10/10

Please make your problem very clear, i guess you are missing something.

Mustak_Shaikh
Avatar of rgill67

ASKER

Both tinchos and n-fortynine were helpful with the switch, thank you...
rgill67,

Would you please explain why you accepted that answer?  The first part was right on about how to do MOD division, but the rest of it won't help you at all.

Dex*
You're welcome rgill67

Glad it helped

Have a nice weekend

Tincho
Sorry dexstar,

But I don't agree with you that my comment won't help at all.

Why are you saying that?

tinchos,

Firstly, I don't mean to offend.  You definitely answered the question that he asked.  I guess that's why he accepted your answer.  That's fine.

My problem is that the answer to that question won't help him solve his problem because a switch statement is not at all appropriate.

> switch( atmChange * 100 )           // 100 if you want to work with the 2 decimal places
> {
>    case 1000:
>                         // Code for 10.00
>    case 100:
>                         // Code for 1.00
>    case 25:
>                         // Code for 0.25
>    case 10:
>                         // Code for 0.10
>    case 5:
>                         // Code for 0.05
>    default:
>                         // Code
> }

What if atmChange = 37.37 ?  Then it will switch on 3737, which doesn't have a corresponding case statement, so it will execute the "default".  How is that going to help you compute the amount of change to give?  The example only will work if you are giving exactly 10 dollars, 1 dollar, 25 cents, 10 cents, 5 cents, or a penny in change.  If you want to figure out how to give out $37.37, it won't work at all.

Anyway, I guess he got the answer to his question, but after he plays with it for a while, he'll figure out that it isn't going to work using a switch statement, and he'll have to come back to ask another question.  No, wait, he won't because I already gave him the answer.  Oh well.  It's just points.

Dex*