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passing arrays / updating object arrays

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Join Date: Jun 2007

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Reputation: Hamrick will become famous soon enough

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Hamrick

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Posting Whiz

Re: passing arrays / updating object arrays

#31

Sep 6th, 2007

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toppings[z] = a[z] ;
toppings[z] = a[z] ;

If a is declared as a plain int, why are you subscripting it like an array of int? I think you should make the whole thing an array and that'll fix your problem.

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void Pizza::set ( int x , int y , int a[] , int i );
void Pizza::set ( int x , int y , int a[] , int i );

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void Pizza::set ( int x , int y , int a[] , int i )
{
    type = x ;
    size = y ;
    for ( int z = 0 ; z < i ; z++ )
        toppings[z] = a[z] ;
}
void Pizza::set ( int x , int y , int a[] , int i )
{
    type = x ;
    size = y ;
    for ( int z = 0 ; z < i ; z++ )
        toppings[z] = a[z] ;
}

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pizza.set ( x , y , a, i ) ;
pizza.set ( x , y , a, i ) ;

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Join Date: Jun 2006

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Duki

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Re: passing arrays / updating object arrays

#32

Sep 6th, 2007

awesome!! It's working now!
Now I just need to do some slight modifications and add the computePrice function and I'm done.

thanks everyone!!

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Dave Sinkula Dave Sinkula is offline

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Re: passing arrays / updating object arrays

#33

Sep 6th, 2007

I thought you had declared the third parameter as a reference to an array?

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void Pizza::set ( int x , int y , int (&a)[7] , int i )
void Pizza::set ( int x , int y , int (&a)[7] , int i )

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Join Date: Jun 2006

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Duki

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Re: passing arrays / updating object arrays

#34

Sep 6th, 2007

i did but then i found out that c++ passes all arrays by reference by default.

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Hamrick

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Re: passing arrays / updating object arrays

#35

Sep 6th, 2007

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i did but then i found out that c++ passes all arrays by reference by default.

You have to be careful here. 'By reference' could mean two things, and only one of them is right.

Thef irst by reference is an actual reference in C++ and arrays are not passed by that reference by default. To pass an array by actual reference in C++ you do it like Dave said.

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
void Pizza::set ( int x , int y , int (&a)[7] , int i )
void Pizza::set ( int x , int y , int (&a)[7] , int i )

The second by reference is a fake reference that you get by passing a pointer by value and being able to get to the thing that the pointer points to. That's the default for arrays and that's why all of these are the same prototype.

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
void Pizza::set ( int x , int y , int a[7] , int i )
void Pizza::set ( int x , int y , int a[] , int i )
void Pizza::set ( int x , int y , int *a , int i )
void Pizza::set ( int x , int y , int a[7] , int i )
void Pizza::set ( int x , int y , int a[] , int i )
void Pizza::set ( int x , int y , int *a , int i )