Algorithms-Library/heap_sort.cpp at main · Peeyushshar/Algorithms-Library · GitHub

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#include<iostream>
using namespace std;
void maxHeapify(int heap[],int i,int n)
{
    int left=2*i;
    int right=2*i+1;
    int largest=i;
    if(left <=n && heap[i]<heap[left])
    largest = left;
    if(right <=n && heap[largest]<heap[right])
    largest = right;                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              right;
    if(largest !=i)
    {
        int temp=heap[largest];
        heap[largest]=heap[i];
        heap[i]=temp;
        maxHeapify(heap,largest,n);

    }

}
void buildHeap(int heap[],int n)
{
    for (int i=n/2;i>=1;i--)
    maxHeapify(heap,i,n);

}
int main()
{
    int n;
    cout<<"Number of elements";
    cin>>n;
    int heap[n+1];
    cout<<"Enter elements"<<endl;
    for(int i=1;i<=n;i++)
    cin>>heap[i];
    buildHeap(heap,n);
    int heapsize=n;
    for(int i=n;i>=2;i--)
    {
        int temp=heap[1];
        heap[1]=heap[i];
        heap[i]=temp;
        --heapsize;
        maxHeapify(heap,1,heapsize);

    }
    cout<<" After sorting "<<endl;
    for(int i =1;i<=n;i++)
    cout<<heap[i]<<" ";
    return 0;
}