heap_sort(48).cpp

#include <iostream>
using namespace std;
 
class heap
{
public:
void heapify(int arr[], int n, int i)
{
    int largest = i;  // Initialize largest as root
    int l = 2*i + 1;  // left = 2*i + 1
    int r = 2*i + 2;  // right = 2*i + 2
 

    if (l < n && arr[l] > arr[largest])
        largest = l;
 

    if (r < n && arr[r] > arr[largest])
        largest = r;
 

    if (largest != i)
    {
        swap(arr[i], arr[largest]);
 
     heapify(arr, n, largest);
    }
}
 

void heapSort(int arr[], int n)
{
for (int i = n / 2 - 1; i >= 0; i--)
        heapify(arr, n, i);
 
  
    for (int i=n-1; i>=0; i--)
    {
       
        swap(arr[0], arr[i]);
 
       
        heapify(arr, i, 0);
    }
}
 

void printArray(int arr[], int n)
{
    for (int i=0; i<n; ++i)
        cout << arr[i] << " ";
    cout << "\n";
}
};

int main()
{ heap sl;
 int *arr;
 int n;
 cout<<"enter your elements size \n";
 cin>>n;
 arr = new int [n];
 cout<<"\nEnter your elements for heap sort\n ";
 for(int i=0;i<n;i++)
 {
 	cin>>arr[i];
 }
 
 
    sl.heapSort(arr, n);
 
    cout << "Sorted array is \n";
    sl.printArray(arr, n);
}