CPPScratchPad.cpp

// CppScratchPad.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include "pch.h"
#include <iostream>
#include <vector>


using namespace std;

class Resource
{
	int aNumber;
public:
	Resource() : aNumber(3)
	{
		cout << " Resource constructor " << endl;
	}

	~Resource()
	{
		cout << "Resource destructor " << endl;
	}
};

class Foo
{

public:
	int* a;
	int size;

	Foo(int _size = 5) 
	{
		cout << "Foo constructor" << endl;
		a = new int[size];
		size = _size;
	}

	~Foo()
	{
		cout << "Foo destructor" << endl;
		delete [] a;
	}

	Foo(const Foo& other)
	{
		a = new int[other.size];
		size = other.size;
	
		std::copy(other.a, other.a + size, a);

		//a = other.a;
		cout << "Foo copy constructor" << endl;
	}

	int& operator[](int i)
	{
		return *(a + i);
	}

	Foo& operator=(const Foo& other)
	{
		//tear down
		delete[] a;

		// copy
		a = new int[other.size];
		size = other.size;

		std::copy(other.a, other.a + size, a);

		//a = other.a;
		cout << "Foo copy assignment constructor" << endl;
		return *this;
	}

	void DebugFoo()
	{
		cout << "Foo.a is " << endl;
		for (int i = 0; i < size; ++i)
			cout << *(a + i) << ", ";

		cout << "done" << endl;
	}

};

void ErrorsWithFoo()
{
	Foo f;
	*(f.a + 1) = 3;
	f.DebugFoo();
	{
		Foo g(f);
		g.DebugFoo();

		{
			Foo h;
			h = g;
			h.DebugFoo();
		}
	}
}



class Cube
{
public:
	int size;

	Cube(int _size)
	{
		size = _size;
	}

	Cube()
	{
		size = 0;
	}

	Cube operator+(const Cube& other)
	{
		Cube c;
		c.size = size + other.size;
		return c;
	}

	
};

void ShowTheConstructors()
{
	{
		Foo f;
		Foo g(f);
		Foo h;
		h = g;
	}
	cout << "pointers " << endl;

	{
		Foo* pF = new Foo();
		delete pF;
	}
}

void AddMany(vector<int>& vec)
{
	for (int i = 0; i < 4; ++i)
	{
		vec.push_back(i);
	}
}

void MakeDanglingPointers()
{

	vector<int> v;
	v.push_back(3);
	int *first = &v[0];
	AddMany(v);

	cout << " first elem is: " << *first << endl;

}



void MessWithTheStack()
{
	
}

int main()
{
    cout << "Hello World!\n"; 

	//ShowTheConstructors();
	ErrorsWithFoo();

	//MakeDanglingPointers();
	//MessWithTheStack();

	//Foo f;
	//int input;
	//cin >> input;
	//cout << "f.a " << f.res << endl;

}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started: 
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file