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{
This is the test Program that I drew up to test the Procedures in Pete
Davis' LinkList.Pas posted in the previous message. It could be a little more
dressed up but it does work and offers some insight, I think, into the use of
Pointers and linked lists: note that I ran a little manual test to locate a
designated Pointer in a given list. Here it is:
}
Uses
Crt, LinkList;
Var
AList1, AList2, AList3, AList4 : Data_Ptr;
ANum : DataType;
Count : Integer;
begin
ClrScr;
Init_List(AList1);
Writeln('Results of inserting links at the beginning of a list: ');
For Count := 1 to 20 do
begin
ANum := Count;
Write(' ',ANum);
Insert_begin(AList1, ANum); {pay out first link (1) to last (20) like}
{a fishing line With #-cards. You end up}
end; {with 20 in your hand going up to 1}
Writeln;
Writeln('Watch - Last link inserted is the highest number.');
Writeln('You are paying out the list like reeling out a fishing line,');
Writeln('Foot 1, Foot 2, Foot 3, etc. - last one is Foot 20.');
Writeln('Now, mentally reel in the line to the fourth number.');
Writeln(' ',alist1^.Next_Rec^.Next_Rec^.Next_Rec^.OurData);
Writeln;
Writeln('Now insert one additional number at beginning of list');
begin
ANum := 21;
Insert_begin(AList1,ANum);
end;
Writeln(' ',AList1^.OurData);
Writeln;
Init_List(Alist2);
Writeln('Results of Inserting links in turn at the end of a list: ');
For Count := 1 to 20 do
begin
ANum := Count;
Write(' ',ANum);
Insert_end(Alist2,ANum);
end;
Writeln;
Writeln('note, just the reverse situation of the process above.');
Writeln('Reel in the line to the fourth number.');
Writeln(' ',Alist2^.Next_Rec^.Next_Rec^.Next_Rec^.OurData);
{We inserted at the end so we are now going out toward the 20}
Init_List(Alist3);
Writeln('Results of Inserting links in turn in orDER');
For Count := 1 to 20 do
begin
Anum := Count;
Write(' ',ANum);
Insert_In_order(Alist3,ANum);
end;
Writeln;
Writeln(' ',Alist3^.Next_Rec^.Next_Rec^.Next_Rec^.OurData);
end.
{
In Case anybody missed Pete Davis' Linklist Unit in the previous
message but may have it in her/his library (PNL002.ZIP) what I was asking is
some help With writing code to test the Procedure DELETE_HERE which is the last
Procedure in the Unit.
}
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