HeapSort.cpp

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

maxHeapify(int A[],int i, int heapSize)
{
 int largest=i;
 int l=2*i+1;
 int r=2*i+2;
 if(l<heapSize && A[l]>A[largest])
 largest=l;
 if(r<heapSize && A[r]>A[largest])
 largest=r;
 if(largest!=i)
 {
 swap(A[largest],A[i]);
 maxHeapify(A,largest,heapSize);
 }
}
BuildMaxHeap(int A[],int heapSize)
{
 for(int i=(heapSize/2)-1;i>=0;i--)
 maxHeapify(A,i,heapSize);
}
HeapSort(int A[],int heapSize)
{
 BuildMaxHeap(A,heapSize);
 for(int i=heapSize-1;i>=0;i--)
 {
 swap(A[0],A[i]);
 heapSize--;
 maxHeapify(A,0,heapSize);
 }
}
int main()
{
 int n;
 cout<<"Enter the no of nodes : "<<endl;
 cin>>n;
 int A[n];
 int heapSize=sizeof(A)/sizeof(A[0]);
 cout<<"Enter the nodes"<<endl;
 for(int i=0;i<n;i++)
 cin>>A[i];
 HeapSort(A, heapSize);
 for(int i=0;i<n;i++)
 cout<<A[i]<<" ";
}