Question

Write a program in prolog to delete all reference of a particular item from a list. It should have three arguments. The list you wish to use, the item to delete, and the resulting list. Here are some example of it behaviour

?- delete_all([a,b,a,c,a,d],a,Result).

Result = [b,c,d]

? - delete_all([a,b,a,c,a,d],b,Result).

Result = [a,a,c,a,d]

Answer 1

delete_all([],_,[]):-!.   %If list is empty then Resultant list is also empty
delete_all([Elem|T],Elem,R):- delete_all(T,Elem,R).   %If Head of the list is same as Element to be deleted, Remove It
delete_all([H|T],Elem,[H|R]):-H \= Elem, delete_all(T,Elem,R).   %move ahead

/* OUTPUT */

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