how should i identify this parameter from a struct inside a function from class?

[Deeyumm]

I'm trying to write the set() function and the parameter of it should be length which is part of the struct i tried to call length using the words array/items/price but none of them seemed to work
i need help in identifying my mistakes and fixing my errors

#include<iostream>
using namespace std;

struct array
{
    int length, *p;
};
class pharmacy
{
private:
    array items, price;
    int totalsales;
public:
    void set(int);
    void print();
    void calculatetotalsales();
    pharmacy(int length=1);
    ~pharmacy();
    pharmacy(const pharmacy&);

};
int main()
{
	pharmacy *obj, pObject;
	obj = &pObject;
	obj -> set(3);
	obj -> print();
	return 0;
}

void pharmacy::set(int l)
{
    length=l;
    items= new array[items.length];
    cout<<"Enter quantities and price or 3 items: "<<endl;
    for(int i=0; i<array.length; i++)
    {
        cout<<"item#"<<i+1;
        cin>>items[i]<<price[i];
    }
    calculatetotalsales();
}
void pharmacy::calculatetotalsales()
{
    totalsales=0;
    for(int i=0; i<length; i++)
    {
        totalsales+=(items[i]*price[i]);
    }
}

[Chervil]

There are two lengths involved, because at line 12 two array objects are declared

array items, price;

Function set() might look like this:

void pharmacy::set(int l)
{
    items.length = l;
    items.p = new int[items.length];
    
    price.length = l;
    price.p = new int[price.length];
    
    cout<<"Enter quantities and price for " << items.length << " items: "<< endl;

    for(int i=0; i<items.length; i++)
    {
        cout << "item#" << i+1;
        cin >> items.p[i] >> price.p[i];
    }
    calculatetotalsales();
}

That seems less than ideal as it is then the programmer's responsibility to make sure that the two separate lengths are always identical. You might want to consider a change to the design, so that just a single length is needed.