#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;
}
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