#include <iostream>

using namespace std;


/**
 * This program illustrates the difference between pointer arithmetic and integer arithmetic on ints (size 4 bytes on 32 bit machine)
 * and floats (size 8 bytes on 32 bit machine)
 */
int main()
{  
  const int N = 10;
 

  // Work with int pointers first
  {
	cout << endl 
		 << "Int Size: " << sizeof(int) << endl << "-----------" << endl;
	
	int arr[N] = {1,1,2,3,5,8,13,21,34,56};
	
	
	// First do not cast the pointers, what happens?
	cout << "\n   pointer arithmetic\n   -------------------\n";
	{
	  int *end = arr;
	  for (int i=0;i<N;i++) {
		end++;
		cout << "   " << i << ": " << end << " - " << arr << " = " << end - arr << endl;
	  }
	}
	
	// Now cast the pointers to ints, what happens?
	cout << "\n   int arithmetic\n   ---------------\n";
	{
	  int *end = arr;
	  int startInteger = (int) arr;
	  
	  for (int i=0;i<N;i++) {
		end++;
		int endInteger = (int) end;
		cout << "   " << i << ": (int) " << end << " - (int) " << arr << " = " << endInteger - startInteger << endl;
	  }
	}
  }
  

  // Now work with double pointer
  {
	cout << endl
		 << "Double Size: " << sizeof(double) << endl << "--------------" << endl;
  
	double arr[N] = {1,1,2,3,5,8,13,21,34,56};
	
	// Not casting will work the same as ints, but what about when we cast the pointers to ints?
	cout << "\n   int arithmetic\n   ---------------\n";
	{
	  double *end = arr;
	  int startInteger = (int) arr;
	
	  for (int i=0;i<N;i++) {
		end++;
		int endInteger = (int) end;
		cout << "   " << i << ": (int) " << end << " - (int) " << arr << " = " << endInteger - startInteger << endl;
	  }
	}
  }
}