Write a Program of Heap Sorting Algorithm in C++.

HEAP SORT

#include<iostream>

using namespace std;

#include<conio.h>

void max_heapify(int *a, int i, int n)

{

    int j,temp;

    temp=a[i];

    j=2*i;

    while(j<=n)

    {

                        if(j<n && a[j+1]>a[j])

                                    j=j+1;

                        if(temp>a[j])

                                    break;

                        else if(temp<=a[j])

                        {

                                    a[j/2]=a[j];

                        j=2*j;

                        }

    }

    a[j/2]=temp;

    return;

}

void heapsort(int *a, int n)

{

    int i,temp;

    for (i=n;i>=2;i--)

    {

                        temp=a[i];

                        a[i]=a[1];

                        a[1]=temp;

                        max_heapify(a,1,i-1);

    }

}

void build_maxheap(int *a, int n)

{

    int i;

    for(i=n/2;i>=1;i--)

                        max_heapify(a,i,n);

}

main()

{

    int n,i,x;

    cout<<"Enter no of elements of Array:";

    cin>>n;

    int a[20];

    for (i=1;i<=n;i++)

    {

                        cout<<"Enter element "<<(i)<<":";

                        cin>>a[i];

    }

    build_maxheap(a,n);

    heapsort(a, n);

    cout<<"Sorted output.....\n";

    for (i=1;i<=n;i++)

                        cout<<a[i]<<"          ";

    getch();

}

OUTPUT