for (k = kh_begin(rg2smid); k != kh_end(rg2smid); ++k)
if (kh_exist(rg2smid, k)) free((char*)kh_key(rg2smid, k));
kh_destroy(sm, sm->rg2smid);
for (k = kh_begin(rg2smid); k != kh_end(rg2smid); ++k)
if (kh_exist(rg2smid, k)) free((char*)kh_key(rg2smid, k));
kh_destroy(sm, sm->rg2smid);