Heap_sort.cpp

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

void heapify(int arr[], int N, int i)
{
    int largest = i;
    int left = 2 * i + 1;
    int right = 2 * i + 2;

    if (left < N && arr[left] > arr[largest])
        largest = left;
    if (right < N && arr[right] > arr[largest])
        largest = right;
    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);
    }
}

int main()
{
    int n;
    cout << "Enter size of Array: ";
    cin >> n;
    int arr[n];
    cout << "Enter " << n << " Elements: ";
    for (int i = 0; i < n; i++)
    {
        cin >> arr[i];
    }
    cout << "Applying Heap Sort.....\n";
    heapSort(arr, n);
    cout << "Sorted...\n";
    for (int i = 0; i < n; i++)
    {
        cout << arr[i] << " ";
    }
    return 0;
}