Returns all successive size length permutations of the input iterator. The permutations are emitted in lexicographic
ordering according to input. So if input is sorted, the permutations will be in sorted order.
Elements in the permutations are treated as unique based on their position in the iterator, not on their value. So
if the input iterator is unique, then there will be no repeat values.
Returns all successive
sizelength permutations of the input iterator. The permutations are emitted in lexicographic ordering according to input. So if input is sorted, the permutations will be in sorted order. Elements in the permutations are treated as unique based on their position in the iterator, not on their value. So if the input iterator is unique, then there will be no repeat values.