#include <iostream>
#include <string>
#include <locale>
#include <codecvt>

int main() {
	
	std::string s="абв.";
	std::cout << s.size() << std::endl;
	
	char a[3];
	a[0] = s[0];
	a[1] = s[1];
	a[2] = 0;
	
	std::cout << a << std::endl;
	
	std::wstring_convert<std::codecvt_utf8<char32_t>, char32_t> convert;
	
	std::u32string utf32 = convert.from_bytes(s);
	
	std::cout << utf32.size() << std::endl;
	
	std::u32string temp;
	
	for (int i= utf32.size() - 1; i > -1; i--) temp.push_back(utf32[i]);
	
	std::string utf8 = convert.to_bytes(temp);
	
	std::cout << utf8;
	
	return 0;
}