### 11.5 Multiset functions

Function: int gsl_multiset_next (gsl_multiset * c)

  This function advances the multiset c to the next multiset element in lexicographic order and returns `GSL_SUCCESS`. If no further multisets elements are available it returns `GSL_FAILURE` and leaves c unmodified. Starting with the first multiset and repeatedly applying this function will iterate through all possible multisets of a given order.

Function: int gsl_multiset_prev (gsl_multiset * c)

  This function steps backwards from the multiset c to the previous multiset element in lexicographic order, returning `GSL_SUCCESS`. If no previous multiset is available it returns `GSL_FAILURE` and leaves c unmodified.