Integers are read and stored in a linked list. The input stops when the number 0 is entered, and the stored integers are printed in the following format: 1 → 2 → …

The code is:

program ZeigerEinlesenEcho (input, output);

type
    PointerElement = ^Element;
    Element = record
        Data : integer;
        Next : PointerElement
    end;

var
    Start, Last, Current : PointerElement;
    Zahl, Counter : integer;
    
begin
    new (Start);
    Current := Start;
    writeln('Dieses Programm erstellt eine Liste ganzer Zahlen.');
    writeln('Gib eine ganze Zahl ein (Die Zahl 0 bricht die Eingabe ab): ');
    readln(Zahl);
    
    while Zahl <> 0 do
        begin
    new (Last);
    Current^.Data := Zahl;
    Current^.Next := Last;
    Current := Last;
    readln(Zahl);
    end;
                
    Current^.Next := nil;
    Current := Start;

    Counter := 0;
    while Current <> nil do
        begin
    Counter := Counter + 1;
    write(Counter, '. ',Current^.Data,' -->  ' );
    Current := Current^.Next;
    end;
    writeln();
    write('Die letzte Eingabe war: ', Zahl, Current^.Data);
end.

I expected the output to be the integers that I entered: 1 → a → 2 → b → … where a and b are the read integers.

The entered integers are printed correctly, but additional unexpected integers and an error code appear at the end.

The output is:

Free Pascal Compiler version 3.2.0 [2022/02/07] for x86_64
Copyright (c) 1993-2020 by Florian Klaempfl and others
Target OS: Linux for x86-64
Compiling main.p
Linking main
43 lines compiled, 0.7 sec

Dieses Programm erstellt eine Liste ganzer Zahlen.
Gib eine ganze Zahl ein (Die Zahl 0 bricht die Eingabe ab): 
1
2
3
4
0
1. 1 -->  2. 2 -->  3. 3 -->  4. 4 -->  5. -16168 -->  
Runtime error 216 at $000000000040135D
  $000000000040135D
  $0000000000422FDC

Die letzte Eingabe war: 0