C++ program to implement Shell sort using class

#include<iostream.h>
#include<constream.h>
void read(int a[10],int n)
{
	cout<<"reading\n";
	for(int i=0;i<n;i++)
		cin>>a[i];
}
void display(int a[10],int n)
{
	for(int i=0;i<n;i++)
		cout<<a[i]<<"\t";
}
void shellsort(int a[10],int n)
{
	int gap=n/2;
	do
	{
		int swap;
		do
 
		{
			swap=0;
			for(int i=0;i<n-gap;i++)
				if(a[i]>a[i+gap])
				{
					int t=a[i];
					a[i]=a[i+gap];
					a[i+gap]=t;
					swap=1;
				}
		}
		while(swap);
	}
	while(gap=gap/2);
}
void main()
{
	int a[10];
	int n;
	clrscr();
	cout<<"enter n\n";
	cin>>n;
	read(a,n);
	cout<<"before sorting\n";
	display(a,n);
	shellsort(a,n);
	cout<<"\nafter sorting\n";
	display(a,n);
	getch();
}