How to add to end of list in prolog

prolog

Solution

Prolog implements a relational computation model, and variables can only be instantiated, not assigned. Try

?- letters(Stored),
   insertAtEnd(d, Stored, Updated),
   write(Updated).

Problem

I am trying to add one item to the end of a list in prolog, but it keeps on failing. ``` insertAtEnd(X,[ ],[X]). insertAtEnd(X,[H|T],[H|Z]) :- insertAtEnd(X,T,Z). letters([a,b,c]). ``` I do not understand why this below does not work. ``` insertAtEnd(d,letters(Stored),letters(Stored)). ``` I am also attempting to store this list in the variable Stored throughout, but I am not sure if the above is correct way to proceed.

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