// 전역 locale 설정
std::locale::global(std::locale(""));

std::string mbs1 = "abcdef가나다라";
std::wstring wcs1 = L"abcdef가나다라";
std::string mbs2 = wcs_to_mbs(wcs1);
assert(mbs1 == mbs2);
std::wstring wcs2 = mbs_to_wcs(mbs1);
assert(wcs1 == wcs2);