#include <iostream>
#include <string>
#include <regex>

int main() {
	std::string test = "ℕ";
	test = std::regex_replace(test, std::regex(""), "z");
	std::cout << test << "\n";
	
	test = "𝔸";
	test = std::regex_replace(test, std::regex(""), "z");
	std::cout << test << "\n";
	
	test = "v̂";
	test = std::regex_replace(test, std::regex(""), "z");
	std::cout << test << "\n";

	return 0;
}