#include <string>
#include <sstream>
#include <iostream>
#include <class T>
std::string to_string(T t, std::ios_base & (*f)(std::ios_base&))
{
std::ostringstream oss;
oss << f << t;
return oss.str();
}
int main()
{
std::cout<<to_string<long>(123456, std::hex)<<std::endl;
std::cout<<to_string<long>(123456, std::oct)<<std::endl;
return 0;
}