#include <iostream>
#include <string>
#include <regex>
 
int main()
{
    std::regex pattern { "a" };
    std::cout << "'a' match with 'ab': " << std::boolalpha << 
        std::regex_match("ab", pattern) << std::endl;
    
    std::cout << "search 'a' in 'ab': " << std::boolalpha << 
        std::regex_search("ab", pattern) << std::endl;
}