=====prev_permutation=====
Syntax:

<code>
    #include <algorithm>
    bool prev_permutation( bidirectional_iterator start, bidirectional_iterator end );
    bool prev_permutation( bidirectional_iterator start, bidirectional_iterator end, StrictWeakOrdering cmp );
</code>

The prev_permutation() function attempts to transform the given range of
elements [start,end) into the next lexicographically smaller permutation of
elements. If it succeeds, it returns true, otherwise, it returns false.

If a strict weak ordering function object cmp is provided, it is used instead
of the < operator when comparing elements.

Related Topics: [[next_permutation]], [[random_sample]], [[random_sample_n]], [[random_shuffle]]