Format a number with thousand separator characters in C++

The following code function snippet is an example of how format a number (already in std::string form) with thousand separator characters in C++:

Note: it doesn’t currently support numbers with decimal places, only integer-formatted numbers.

std::string formatNumberThousandsSeparator(const std::string& value)
{
	std::string final;
	int i = value.size() - 1;
	unsigned int count = 0;
	for (; i >= 0; i--)
	{
		final += value[i];

		if (count++ == 2 && i != 0)
		{
			final += ",";
			count = 0;
		}
	}

	std::reverse(final.begin(), final.end());

	return final;
}