#include <iostream>
#include <string>
#include <regex>
 
int main()
{
    std::string text("bbcaXXXXXY");
 
      std::regex ex("([abc]{2,4})(.{1})X*.");
//std::regex ex("(....)(.)X*.");
 
        std::smatch results;
        if( std::regex_match(text, results, ex) )
        {
                auto index = 0;
                for( auto sub : results )
                {
                        if( ++index == 1 ) // whole match
                                continue;
 
                        std::cout << "----" << std::endl;
                        if( sub.matched )
                        {
                                std::cout << sub.str() << std::endl;
                        }
                        else
                                std::cout << "残念" << std::endl;
                }
        }
}
 

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