Currency Conversion using OO

[Willing 2 Learn]

I'm still having trouble getting my program to do arithmetic in
cents(keeping all #'s) then convert the answer in a format of dollars &
cents. The main program should add, subtract, scalar multiply(by int)&
show, have a constructor w/ & w/out arguments. Header file should have
private data & all 6 functions from above.Class definition file should
implement my ADT class.
What I have so far:
Main program
#include "jahcurrency.h"
#include <iostream.h>
void main()
{
Currency a(4,3);
Currency b(2,1);
Currency total;

total=a.add(b);
total.show();
total=a.sub(b);
total.show();
total=a.multiply(5);
total.show();
}
Header file
class Currency
{
private:
double cents;
public:
Currency();
Currency(int d,int c);
Currency add(Currency b);
Currency sub(Currency b);
Currency multiply(double d);
double calc(Currency s);
double calc2(Currency f);
void show(void);
};
Class definition
#include "jahcurrency.h"
#include <iomanip.h>
#include <math.h>
#include <iostream.h>

char sign='$';


Currency::Currency()
{
x=0;

}
Currency::calc2(Currency f)
{

f=(x*100)-(x%100);

return f;
}
Currency::calc(Currency s)
{

s=(x%100);

return s;

}
Currency::Currency(int d, int c)
{

d=(x*100)-(x%100);
c=(x%100);

return d;

}


Currency::add(Currency b)
{
Currency x;
x.cents= x+ b.x;

return x;
}
Currency::sub(Currency b)
{
Currency x;
x.cents= x- b.x;

return x;
}
Currency::multiply(Currency d)
{
Currency x;
x.cents= x*d.x;

return x;
}


Currency::show()
{
cout<<sign<<d<<". "<<s<<endl;
}
How different would the program be if cents is in long then convert
ans. for each opeartion to dollars & cents ?
Your help would be appreciated in how to fix this problem.

 

[osmium]

I'm still having trouble getting my program to do arithmetic in
cents(keeping all #'s) then convert the answer in a format of dollars &
cents. The main program should add, subtract, scalar multiply(by int)&
show, have a constructor w/ & w/out arguments. Header file should have
private data & all 6 functions from above.Class definition file should
implement my ADT class.
What I have so far:
Main program
#include "jahcurrency.h"
#include <iostream.h>
void main()
{
Currency a(4,3);
Currency b(2,1);
Currency total;

total=a.add(b);
total.show();
total=a.sub(b);
total.show();
total=a.multiply(5);
total.show();
}
Header file
class Currency
{
private:
double cents;

Fatal flaw. Even if you get it to work it will not be usable. People are
very fussy about money and they want totals to add up to 100.0%. A double
is only an *approximation* of a real number.

Also, Currency is a bad name for the class. You have gone to great pains to
handle coins. In common usage currency is paper money. How about "Money"
as a name?

<anip>

 

[Bob Hairgrove]

I'm still having trouble getting my program to do arithmetic in
cents(keeping all #'s) then convert the answer in a format of dollars &
cents. The main program should add, subtract, scalar multiply(by int)&
show, have a constructor w/ & w/out arguments. Header file should have
private data & all 6 functions from above.Class definition file should
implement my ADT class.
What I have so far:
Main program
#include "jahcurrency.h"
#include <iostream.h>

#include <iostream> /* WITHOUT the H */

Including STL headers with .h ending is deprecated and can lead to
many problems.

void main()

int main()

The C++ standard requires that main() return int.

{
Currency a(4,3);
Currency b(2,1);
Currency total;

total=a.add(b);
total.show();
total=a.sub(b);
total.show();
total=a.multiply(5);
total.show();
}
Header file
class Currency
{
private:
double cents;
public:
Currency();
Currency(int d,int c);
Currency add(Currency b);

Should be:
Currency add(Currency b) const;
Do you know why? You need to know...

Currency sub(Currency b);
Currency multiply(double d);
double calc(Currency s);
double calc2(Currency f);
void show(void);

void show() const;

};
Class definition
#include "jahcurrency.h"
#include <iomanip.h>
#include <math.h>
#include <iostream.h>

#include <iomanip>
#include <iostream>


char sign='$';


Currency::Currency()
{
x=0;

Where is x declared? What about your member variable cents??

}
Currency::calc2(Currency f)
{

f=(x*100)-(x%100);

return f;
}
Currency::calc(Currency s)
{

s=(x%100);

return s;

}
Currency::Currency(int d, int c)
{

d=(x*100)-(x%100);
c=(x%100);

return d;

???
You can't return anything from a constructor.
And you throw away the second calculation, so what good is it?

}


Currency::add(Currency b)

Should be:
Currency Currency::add(Currency b) const

{
Currency x;
x.cents= x+ b.x;

return x;
}
Currency::sub(Currency b)

Same as above...

{
Currency x;
x.cents= x- b.x;

return x;
}
Currency::multiply(Currency d)
{
Currency x;
x.cents= x*d.x;

return x;
}


Currency::show()
{
cout<<sign<<d<<". "<<s<<endl;
}
How different would the program be if cents is in long then convert
ans. for each opeartion to dollars & cents ?
Your help would be appreciated in how to fix this problem.

Did you try to compile this before posting?
I didn't think so...