#include "List.h"

List append(List L1, List L2)
/* NB. L1 & L2 are not changed but L2 is shared with the result.  L.Allison */
 { if(L1==NULL) return L2;
   /*else*/ return cons(L1->hd, append(L1->tl, L2));
 }

/* Append Two Lists, L1 and L2 */