Algorithms/Heapsort.cpp at main · shrivardha/Algorithms · GitHub

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//heap sort
#include<bits/stdc++.h>
using namespace std;

void heapify(int arr[], int n, int i)
{

    int largest = i;

    int l = 2 * i + 1;

    int r = 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()
{
    int n;
    cout << "Enter the size of array :\n";
    cin >> n;

    cout << "\n\nEnter the elements of array : \n";
    int a[n];

    for(int i = 0 ; i < n ; i++)
        cin >> a[i];

    heapSort( a, n );

    cout << "\n\nSorted array is :\n";
    printArray( a , n);

    return 0;
}