Question

Define a Prolog predicate project/3 that selects elements from a list by their position and collects them in a result list. For example, the goal of project([2,4],[a,b,c,d],L) should produce the answer L=[b,d]. You can assume that the numbers in the first list are strictly increasing, that is, your implementation does not have to care about situations like project ([1,1,2],..)orproject([2,5,3],..).

Answer 1

In Prolog, you can define the predicate project/3 to select elements from a list by their position and collect them in a result list.

Step-by-step explanation:

In Prolog, you can define the predicate project/3 to select elements from a list by their position and collect them in a result list. Here is an example implementation:

project([], _, []).
project([Index|Rest], List, [Element|Result]) :-
nth1(Index, List, Element),
project(Rest, List, Result).

With the project/3 predicate, you can call project([2,4],[a,b,c,d],L) to get L=[b,d]. The predicate recursively extracts the elements from the given positions using the nth1/3 predicate in Prolog.

The prolog append predicate syntax is shown below. name([value1, value2, value3], [value4, value5, value6], [value1, value2, value3, value4, value5, value6]). The basic prolog intersection predicate syntax is shown below. name([value1, value2, value3], [value4, value1, value6], Result).

Prolog programs are built from valid Prolog data-structures. A program is a collection of predicates, and a predicate is a collection of clauses. The idea of a clause is to define that something is true. The simplest form of a clause is the fact.