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Accessing an array present in a class using pointers

#include <iostream>

using namespace std;

class sort_overload
{
    int a[10];
public:
    void sort(int ,int);
    void display();
    void getdata();
}s;

void sort_overload::sort(int first,int last) //quick sorting
{
    int sort_overload :: *sp = &sort_overload :: a[0]; //pointer to the         base address of a present in class sorted_overload

sort_overload *sp_obj = &s; 
int pivot = sp_obj->*(sp+last);
int i=first,j=last;
int temp;

if(i<j)
{

    while((sp_obj->*(sp+i)) < pivot)
        i++;
    while((sp_obj->*(sp+j)) > pivot)
        j--;
    if(i<j)
    {
        temp = (sp_obj->*(sp+i));
        (sp_obj->*(sp+i)) = (sp_obj->*(sp+j));
        sp_obj->*(sp+j) = pivot;
        sp_obj->*(sp+last)=temp;
    }
}

    s.sort(first,j-1);
    s.sort(j+1,last);

}
void sort_overload::display()
{
    int sort_overload :: *sp = &sort_overload :: a;
    sort_overload *sp_obj = &s;
    for(int i=0;i<10;i++)
        cout<<"Sorted array numbers:"<<sp_obj->*(sp+i)<<endl;

}
void sort_overload::getdata()
{
    int sort_overload:: *sp = &sort_overload :: a;
    sort_overload *sp_obj = &s;
    cout<<"Enter numbers";
    for(int i=0;i<10;i++)
        cin>>sp_obj->*(sp+i);
}

int main()
{
    s.getdata();
    s.sort(0,9);
    s.display();
    return 0;
}

This statement gives me an error:

int sort_overload :: *sp = &sort_overload :: a[0];

Could somebody tell me why the error is coming up?

I'm trying to sort 10 integer values, and further overload it to sort double and float values as well, but I am stuck on the sorting part.

Since

void sort_overload::sort(int first,int last)

is a member function of your class, you can can access your array by replacing

int sort_overload :: *sp = &sort_overload :: a[0];

by

int *sp = this->a;

or better just use this->a instead of sp

You cannot use the syntax :

&sort_overload :: a[0];

because your array is not a static attribute.

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