/***CODE THIS ONLY IN PRO-LOG PROGRAMMING LANGUAGE***//

//*** IT'S VERY LESS CODE BUT YOU SHOULD USE ONLY PRO-LOG PROGRAMMING PLEASE DON'T GIVE ANSWERS IN OTHER PROGRAMMING LANGUAGES***//

We squash a list L by first removing all lists within L and replacing them with their members then we remove all duplicate values in the list. Write a Prolog rule squash/2 which squashes a list. The items in the output list do not have to be in any specific order. For example:

squash([a,b,c,[d,e],f,[c, a, b]], [d,e,f,c,a,b]).

squash([1,2,3,4,[5,6,[7,8]]], [1,2,3,4,5,6,7,8]).

squash([1,2,[3,4,[5,6],7],8,[2,4,5,8]], [1,3,6,7,2,4,5,8]).