     s_short.replace(s_short.begin(), s_short.begin(), s_short.c_str());     assert(s_short == "000/000/");     s_short.replace(s_short.begin(), s_short.begin(), s_short.c_str());     assert(s_short == "000/000/000/000/");     s_short.replace(s_short.begin(), s_short.begin(), s_short.c_str());     assert(s_short == "000/000/000/000/