Create a predicate split_up/4 that partitions a list into 2 sub-list, the first containing the numbers smaller or equal than the first argument, the second the elements strictly larger. Use green cuts to optimise your program.

Not like this:

?- split_up(5,[7,5,3,2,1,5,9,8,6,4,2], Lo, Hi).
Lo = [5, 3, 2, 1, 5, 4, 2],
Hi = [7, 9, 8, 6] ;
false.

But like this:

?- split_up(5,[7,5,3,2,1,5,9,8,6,4,2], Lo, Hi).
Lo = [5, 3, 2, 1, 5, 4, 2],
Hi = [7, 9, 8, 6].