#include <iostream>

#include "functions.h"

using namespace std;

int main()
{
	// general
	int* pNumber = nullptr; // pointer definition, always initialize a pointer (at least with nullptr)
	pNumber = new int(0); // creates a new integer value on the heap

	cout << "size of pointer: " << sizeof(pNumber) << endl;
	cout << "size of pointer data: " << sizeof(*pNumber) << endl;

	*pNumber = 789;

	//pNumber = new int(0); // BAD BAD - memory leak, because we override an existin g pointer address with a new one without saving or deleting the old one

	// here are 100s lines of code

	if (pNumber != nullptr)
	{
		delete pNumber;
		pNumber = nullptr;
	}

	// pointer as references outside local scope
	int number = 10;
	changeInteger(number);
	number = changeIntegerPerReturn(number);
	changeIntegerPerPointer(&number);
	changeIntegerPerPointer(pNumber);
	changeIntegerPerReference(number);

	return 0;
}