`desing/next_comb`
Enumeration of all the j-element sublists of a list of
given number of elements.
- Input:
- L a list of flags (0,1), providing a
characteristic list for the list whose sublists has to be generated.
- Output:
- a list of flags, the next configuration in the
enumeration. If there is no more sublists to be generated, it
returns the empty list.
The procedure first has to be called with L containing first
j 1's then padding 0's. Afterwards it has to be called with the
previous configuration it gave.