#include <algorithm>
#include <iostream>
#include <iterator>
#include <string>
#include <vector>

std::vector<int> get_digits(std::string const& s)
{
	std::vector<int> result;
	result.reserve(s.length());
	std::transform(s.begin(), s.end(), std::back_inserter(result),
	               [](char const i) { return i - '0'; });
	return result;
}

int main()
{
	auto const result = get_digits("12345");
	std::copy(result.begin(), result.end(),
	          std::ostream_iterator<int>(std::cout, "\n"));
}