Write a rule that partitions a list into 2 lists, left and right, where left contains all elements in the original list that are less than or equal to a given pivot value, and right contains all elements that are greater than the pivot value.
Signature: partition(Left, Right, List, Pivot)
Example:
?- partition(L, R, [1, 2, 3], 2).
L = [1,2]
R = [3]
?- partition(L, R, [1, 2, 3, 4, 5, 6], 6).
L = [1,2,3,4,5,6]
R = []Modify the solution from above to partition based on an index rather than a pivot value. You can also specify a base index that corresponds to the first element in the list. (i.e. 0 based or n based index)
Signature: partitionIndex(Left, Right, List, Index, BaseIndex)
?- partitionIndex(L, R, [a, b, c], 1, 0).
L = [a,b]
R = [c]
?- partitionIndex(L, R, [a, b, c], 1, 1).
L = [a]
R = [b,c]- In Prolog, less than or equal to is
=<, instead of<= - Use
[H|T]to destructure a list - Use
append/3to build up a list. Remember than all 3 arguments toappend/3need to be lists, which means that you need to convert single items into lists using[Item]