Program to illustrate Quick sort in c++

#include<iostream.h>

#include<iomanip.h>

#include<conio.h>

class quicksort

{

    public:

int i,n;

int arr[10];

    public:

void getarray();

int partition(int * ,int ,int);

void sortit(int *, int , int);

void display();

};

void quicksort::getarray()

{

    cout<<"Enter Array size: ";

    cin>>n;

    cout<<"unsorted array: ";

    for(int i=0;i<n;i++){

cin>>arr[i];

    }

}

void quicksort::sortit(int *arr, int p, int r)

{

   if (p < r)

{

    int q=partition(arr, p, r);

    sortit(arr, p, q-1);

    sortit(arr, q+1, r);

}

}

int quicksort::partition(int *arr, int p, int r)

{

   int pivot = arr[r];

   int i = (p-1); // index of smaller element

   for (int j=p; j<=r-1; j++)

   {

   // If current element is smaller than the pivot

    if (arr[j] < pivot)

       {

i++;

// swap a[i] and a[j]

int temp = arr[i];

arr[i] = arr[j];

arr[j] = temp;

       }

    }

    // swap a[i+1] and a[r] (or pivot)

    int temp = arr[i+1];

    arr[i+1] = arr[r];

    arr[r] = temp;

    cout<<"\n\n exchange"<<setw(5)<<arr[r]<<setw(5)<<" and"<< arr[i+1];

    return i+1;

}

void quicksort::display()

{

    cout<<"\n The sorted element :";

    for(int i = 0 ; i < n; i++){

cout<<arr[i]<<" ";

    }

}

void main()

{

    clrscr();

    quicksort qs;

    qs.getarray();

    qs.sortit(qs.arr,0,qs.n-1);

    qs.partition(qs.arr,0,qs.n-1);

    qs.display();

    getch();

}

output:

1.Example : 2 8 6 1 4 3 

2.Example: 10 80 30 90 40 50 70

Quick sort animation video link:

https://www.youtube.com/watch?v=PgBzjlCcFvc&t=109s