11_HeapSort.cpp

#include <bits/stdc++.h>
#include <utility>
using namespace std;
#define endl "\n"
#define ll long long

void maxHeapify(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]);
        maxHeapify(arr, n, largest);
    }
}

void heapSort(int arr[], int n) {
    for (int i = 10 / 2 - 1; i >= 0; i--)
        maxHeapify(arr, n, i);

    for (int i = n - 1; i > 0; i--) {
        swap(arr[0], arr[i]);
        maxHeapify(arr, i, 0);
    }
}
int main() {
    int n = 10;
    int arr[10] = {4, 1, 3, 2, 16, 9, 10, 14, 8, 7};

    cout << "Unsorted Array: ";
    for (int i = 0; i < n; i++)
        cout << arr[i] << " ";
    cout << endl;

    heapSort(arr, 10);

    cout << "Sorted Array: ";
    for (int i = 0; i < n; i++)
        cout << arr[i] << " ";
    cout << endl;

    return 0;
}