Heap Data Structure

//HEAPS
#include<iostream>
using namespace std;


//function to check whether given set of arrays is a max heap or not
int check_heap(int c[],int count, int n)
{
    if( count>(n-2)/2)  
        return 1;
    
    if(c[count]>=c[2*count + 2] && c[count]>=c[2*count +1] && check_heap(c, 2*count + 2, n) && check_heap(c, 2* count +1,n))
        return 1;
 
 return 0; 
} 


void heapify(int arr[], int n, int i) 
{ 
    int largest = i;  
    int l = 2*i + 1;  
    int r = 2*i + 2; 
  
    // If left child is larger than root 
    if (l < n && arr[l] > arr[largest]) 
        largest = l; 
  
    // If right child is larger than largest so far 
    if (r < n && arr[r] > arr[largest]) 
        largest = r; 
  
    // If largest is not root 
    if (largest != i) 
    { 
        swap(arr[i], arr[largest]); 
  
        // Recursively heapify the affected sub-tree 
        heapify(arr, n, largest); 
    } 
} 
  

void heapSort(int arr[], int n) 
{ 
    // Build heap (rearrange array) 
    for (int i = n / 2 - 1; i >= 0; i--) 
        heapify(arr, n, i); 
  
    // One by one extract an element from heap 
    for (int i=n-1; i>0; i--) 
    { 
        // Move current root to end 
        swap(arr[0], arr[i]); 
  
        // call max heapify on the reduced heap 
        heapify(arr, i, 0); 
    } 
} 
  
/* A utility function to print array of size n */
void printArray(int arr[], int n) 
{ 
    for (int i=0; i<n; ++i) 
        cout << arr[i] << " "; 
    cout << "\n"; 
} 

int main()
{
    int i;
    int l1, l2;
    int a[]={16,4,10,14,7,9,3,2,8,1};
    int b[]={16,10,14,7,8,9,3,2,4,1};
    
    l1=sizeof(a)/sizeof(int);
    l2=sizeof(b)/sizeof(int);
    
    int result1=check_heap(a,0,l1);
    int result2=check_heap(b,0,l2);
    
    //check the first array
    if(result1==1)
        cout<<"First case: Is a HEAP\n";
    else
        cout<<"First case: Is not a HEAP\n";
    
    //check the second array
    if(result2==1)
            cout<<"Second case: Is a HEAP\n";
    else
        cout<<"Second case: Is not a HEAP\n";
    
    cout<<"\n";    
    // Heapify
    cout<<"First case: Before heapification:\n";
    printArray(a, l1);
    heapSort(a, l1); 
  
    cout << "Sorted array-1 is \n"; 
    printArray(a, l1);
    cout<<"Heapified................."<<"\n";
    
    heapSort(b, l2);
    
    cout<<"Second case: Sorted array-2 is \n";
    printArray(b, l2);
    


}