#include <iostream>
#include <regex>
using namespace std;
 
int main() {
	std::regex reg("/?([^/]+)/?$");
	std::string s("/home/fypj/build/simple-loops.cc/");
	std::cout << std::regex_replace(s, reg, "/$1/$1/") << std::endl;
 
	return 0;
}
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