Generate Next Number and add to char*

[Armannn]

Hello!

I've tried to create a simple program that would allow me to increment a current integer and replace the last "n characters" in a char*.

However, no matter what I do, it simply outputs the same thing all over.

e.g Index = 1

Output:
XX160001
XX160002
XX160003
XX160004
...
XX160010

Could someone possibly tell me what am I doing wrong here?

#include<iostream>

using namespace std;

int index = 1;
char* GenerateNext()
{
	char* def = new char[9];
	char buffer[9];

	int counter = 0;
	int temp = index;

	while (temp != 0)
	{
		temp /= 10;
		counter++;
	}

	strncpy_s(def, 9, "XX160000", 8 - counter); 
	_itoa_s(counter, buffer, 9, 10);
	strcat_s(def, 9, buffer);

	index++;
	return def;
}

int main() 
{
	char* generated = GenerateNext();
	char* generated2 = GenerateNext();

	cout << generated << endl << generated2 << endl;

	for (size_t i = 0; i < 50; i++)
	{
		cout << GenerateNext() << endl;
	}

	delete[] generated;
	delete[] generated2;

	generated = nullptr; 
	generated2 = nullptr;

	system("PAUSE");
	return 0;
}

[Armannn]

It looks like I have set "_itoa_s" to check the counter (which gets set to 0 on every function call) and that's why it will always print the same number. After replacing "counter" with "index" inside _itoa_s, it seems to have fixed the problem.

#include<iostream>

using namespace std;

int index = 1;
char* GenerateNext()
{
	char* def = new char[9];
	char buffer[9];

	int counter = 0;
	int temp = index;

	while (temp != 0)
	{
		temp /= 10;
		counter++;
	}

	strncpy_s(def, 9, "XX160000", 8 - counter); 
	_itoa_s(index, buffer, 9, 10);
	strcat_s(def, 9, buffer);

	index++;
	return def;
}

int main() 
{
	char* generated = GenerateNext();
	char* generated2 = GenerateNext();

	cout << generated << endl << generated2 << endl;

	for (size_t i = 0; i < 50; i++)
	{
		cout << GenerateNext() << endl;
	}

	delete[] generated;
	delete[] generated2;

	generated = nullptr; 
	generated2 = nullptr;

	system("PAUSE");
	return 0;
}