recursion - Stuck with Prolog -

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I just started learning Prolog One of the exercises wants me to write back / 2, a real meaning is that when the second list argument is behind the first list argument. And I have to use a paste plant to write backwards. 

  Paste ([], L, L). Paste (L-, L2, L3)   
 I worked for hours for this But still the answer is not answered.  
 What do I have here:  
  Behind [H | T], LREV): - Paste ([X | T], X, LRV) backwards ([], []).    
 
 
 Prologues lists are very simple data structures.  
     
  •  An empty list has been marked with atomic  [] .  
  •  A non-empty list structure  '.' / 2> where the first argument is  major  and the second argument is  tail , the second list is not empty or empty.                Has empty list.   
     For non blank lists  
       
    •   [a]  structure is . '(A, []) <
    •  
    •   [a, b]  is the structure . '(A,'. '(B, [])) <(A,'. '(B,'. '(C, []))  
    •   [a] , b, c]  structure is .) <
    •  
    •    tail]  absolutely  '.' (Head, tail) .  
    •   [one | [B, c]]  is exactly  [a, b, c]  and t is equal to  '.' (A, '.' (B, '.' (C, [])    
       It is easy to see why someone may prefer a little syntax Chinese .  
       The structure of a list, more like a classic link list ... traditional ... languages, makes it trivial to add and remove items from the head (left) at the end of an existing list  
       One should note that if you  delete  items from a list at a time and  add  you  reverse  Order incentives They produce a list.  
       A common proplog phrase is the use of an  subsidiary  or  accumulator  argument that governs through resurgence is often This assistant will be given preference with the initial value. Anyone can also keep in mind that most recurring problems have one or two  special cases  and the broad  normal  case. / P> 
       Such a thing as such mentioned:  
        paste ([], r Rs.)% Special case: If unite accumulator with the source list is empty, then the result. Paste ([X | Xs], t, rs): -% general case: t 1 = [x | T],% - prepaid the head of the current list for temporary, make a new temporary and paste (xs, t1, rs)% - recursion down. Anyone can take care that the second section above can be re-applied for simplicity to remove the apparent construction of new temporary:  
        Paste ([], Rs, Rs.)% Special case: If the source list is empty, unite the creditor with the result. Paste ([x | xs], t, rs): -% General case: Paste (xs, [x | t], rs)% - Include the current head in temporary and recursive down. . Either way, it is necessary to understand that the priority is achieved with the temporary initial blank list ( [] ).   
       Call it this way, then:  
        paste ([a, b, c], [], r)   / 3  
       
        
        
       / Code> Distinguishing, making your  behind / 2  is ingenious:  
        Backwards (L, R): - Paste (L, [], R) It exposes another common projection phrase: a small "public" definition that calls a "private"  worker domination  which is actually all Working Is.

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