100  Pascal User  Manual  Warning:  if a record variable pi i' created by the second form of New,  then this variable must not change  Iii"  variant during program execution.  Assignment to the entire variable i  I  an error; however one can assign to  the components of  pi.  The first step in programmin  I~  a solution to our problem posed  above, is to introduce a pointer var lable. Let it be called  NewP. Then the  statement  New(NewP)  allocates a new variable of type  PI  [son.  Next the new variable, referenced by the pointer NewP, is to be  inserted after the person referenced by  Pt. See Figure 1O.d.  Figure lO.d  Linked List Before Insertion  Insertion is a simple matter of changing the pointers:  Newpi.Next  := Pti.Next;  Pti.Next  := NewP  Figure 10.e illustrates the result.  Figure lO.c  Linked List After Insertion  Newp~  Insert  ••  Person  /  New  ,  ~.  NewP  ~ 