Please help me to solve this problem: I have a list of lists
[[1,2],[3,4]]
How do I get:
[1,3]
[1,4]
[2,3]
[2,4]
Or if I have a list of lists
[[1,2],[3,4],[6,7]]
How do I get:
[1,3,6]
[1,3,7]
[1,4,6]
[1,4,7]
[2,3,6]
[2,3,7]
[2,4,6]
[2,4,7]
You can do something like this:
lists([], []).
lists([[Head|_]|Lists], [Head|L]):-
lists(Lists, L).
lists([[_,Head|Tail]|Lists], L):-
lists([[Head|Tail]|Lists], L).
That is, take the first element of the first list in your input list and continue recursively with the remaining lists. As a second chance, skip that element and redo with the remaining elements.