Troubles deleting dinamically allocated char array

[gedamial]

Hello.

My friend sent me his class for a String:

class EString
{
	char* alphanumerics;
	int size;

public:
	/* CONSTRUCTOR */
	EString(char* mystring)
	{
		int i = 0;
		size = strlen(mystring);

		alphanumerics = new char[size + 1];

		for (i = 0; i<size; i++)
			alphanumerics[i] = mystring[i];

		alphanumerics[i] = '\0';
	}

	/* DESTRUCTOR */
	~EString()
	{
		cout << "I'm calling destructor for: " << this->alphanumerics << endl;
		delete[] alphanumerics;
		cout << "Delete succeeded!" << endl;
		size = 0;
		alphanumerics = nullptr;
	}

	/* ------------ GETTER ------------ */


	inline int getSize() { return size; }


	/* ------------OPERATORS OVERLOADING------------ */

	EString& operator+(EString& other)
	{
		int totalSize = getSize() + other.getSize();

		char* temp = new char[totalSize+1];

		int i = 0;
		for (i = 0; i<getSize(); i++)
			temp[i] = alphanumerics[i];

		for (int t = 0; t < other.getSize(); t++, i++)
		{
			temp[i] = other.alphanumerics[t];			
		}

		temp[i] = '\0';

		alphanumerics = temp;
		size = totalSize;

		return *this;
	}

	friend ostream& operator<<(ostream& OUT, const EString& mystring)
	{
		OUT << mystring.alphanumerics;
		return OUT;
	}
};


int main()
{
	{
		EString nome = "A";
		cout << nome << " size(" << nome.getSize() << ")" << endl;

		EString nome2 = "B";
		cout << nome << " size(" << nome2.getSize() << ")" << endl;

		EString nome3 = nome + nome2;
		cout << nome3 << " size(" << nome3.getSize() << ")" << endl;
	}

	system("pause");
	return 0;
}

Why isn't he able to delete the variable nome that contains "A"?

He has no troubles deleting the "B", why he has deleting "A"?


This is the output in the console: http://prntscr.com/avs4b0

And this is the error: http://prntscr.com/avs48e

[Moschops]

Line 56. You're altering the char pointer inside one of the EStrings you're meant to be concatenating, and then you're returning one of the two EStrings as the whole new Estring.

The EStrings being concatenated shouldn't be changed, and you shouldn't return one of them as the new, concatenated EString. The idea is to make a whole new EString.

[gedamial]

What's happening in tems of computations? It's crashing why? Cause I'm assigning a char* to a char*?

[Moschops]

It crashes because the alphanumerics pointer inside nome and nome3 point to the exact same char array, so you're calling delete on the same memory twice.

[gedamial]

Thanks man!