Find number of swaps for sorting - C++

#include <iostream>
using namespace std;

int InsertionSort(int a[], int size)
{
  int numberOfSwaps = 0;
  
  for(int i = 1; i < size; ++i)
  {
    int key = a[i];
    int j = i-1;
    
    while(j >= 0 && a[j] > key)
    {
      a[j+1] = a[j];
      --j;
      ++numberOfSwaps;
    }
    
    a[j+1] = key;
  }
  
  return numberOfSwaps;
}

void PrintArray(int a[], int size)
{
  for(int i = 0; i < size; ++i)
  {
    cout << a[i] << " ";
  }
  cout << "\n";
}

int main() 
{
  int n;
  cin >> n;
  int a[n];
  
  for(int i = 0; i < n; ++i)
  {
    cin >> a[i];
  }
  
  cout << InsertionSort(a, n);
  
  return 0;
}