<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 12 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-AU link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hi Mark and Mike,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> I am a little late on the scene but have to support Mark here.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The question on stacks is more a puzzle than a reasonable problem for a student to solve in limited time.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The question begins with a picture of a stack to consider....... which suggests the starting position of the problem. Apparently it is in a full state .... and that can be determined from ?????<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Then, a push (23) is introduced. Hang on, I thought we had a stack to consider with 5 elements. Are we adding another 23 or picking up half way through the introduced stack ? <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Where is it suggested that the introduced stack is in a “stack full” state ? <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The push and pop operations are not the problem, just the starting position of the problem. When is the beginning is what got me first. The bold items were no help as I didn’t consider them to be significant.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Also, the item Top (1) might mean top of stack to the writer, but only adds to the confusion as it is not obvious it means the top of the stack when we start with a stack with 5 elements. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I have gone through my 2<sup>nd</sup> year Data Structures textbooks and have a strong recollection of the 1982 exams I did ( why wouldn’t I ?? ) on stacks and data structures and there was always a pointer or arrow (with a value in a variable ) showing the top of a stack at the beginning of a question and the requirement was to draw the stack through the various states after push and pop functions. Apart from that we either have empty or full states. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I can’t see how this question would have helped in any way to show student’s understanding of a stack and its functions.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Kind Regards<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Kevork Krozian<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Edulists Creator Administrator<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>www.edulists.com.au<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>tel: 0419 356 034<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> sofdev-bounces@edulists.com.au [mailto:sofdev-bounces@edulists.com.au] <b>On Behalf Of </b>Mark KELLY<br><b>Sent:</b> Wednesday, 27 April 2011 2:36 PM<br><b>To:</b> Year 12 Software Development Teachers' Mailing List<br><b>Subject:</b> Re: [Year 12 SofDev] Sample Exam Questions<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'>Thanks for the bone, Mike. Woof! It finally let me work out the many assumptions underlying the question: and after all that, I'm not wagging my tail.<br><br>I think the question is far from clear, and I doubt students would make much of it in a real exam.<br> <br>- It does not, for example, say that the stack is zero-based. If one assumes (as I did) that the stack indexing starts at 1, the whole thing changes and nothing makes sense.<br>- It does not indicate what the mysterious bolding of the bottom 2 items is meant to represent. If the examiners invent their own conventions, they should explain them to us.<br>- It does not tell us that the stack pointer in updated <b>before</b> a push/pop instead of being changed afterwards, as often happens. Again, this changes everything.<br>- One has to realise that the stack is expanding from the bottom and not from the top. Stacks are often represented growing in either direction.<br><br>When it comes to real-world stack implementation, there are so many different options such as these that I found the question mind-boggling while I went through the permutations of possible readings.<br><br>Grrr.<o:p></o:p></p><div><p class=MsoNormal>On 21 April 2011 14:45, Mike Brookes <<a href="mailto:mikebr@tpg.com.au">mikebr@tpg.com.au</a>> wrote:<o:p></o:p></p><div><p class=MsoNormal>Hi Mark et Al<br><br>For the question to make sense one has to make the assumption that the stack positions start at the bottom with position zero and go up to position 4 which is the top of the stack. At the start the bottom two (in bold on the PDF) are valid, hence the top of stack pointer showing 1. <br><br>Below is the completed table and the stack at the start and after each step:<o:p></o:p></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width=817 style='width:612.75pt'><tr style='height:15.75pt;min-height:15.75pt'><td width=35 style='width:26.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt;min-height:15.75pt'></td><td width=91 style='width:68.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=31 style='width:23.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=124 style='width:93.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=29 style='width:22.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=31 style='width:23.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=31 style='width:23.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=64 style='width:48.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=64 style='width:48.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=64 style='width:48.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=64 style='width:48.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=64 style='width:48.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=64 style='width:48.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td width=64 style='width:48.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'></td></tr><tr style='height:15.75pt;min-height:15.75pt'><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt;min-height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td colspan=7 style='border:none;border-right:solid black 1.0pt;padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Stack at start and after each step<o:p></o:p></p></td></tr><tr style='height:15.75pt;min-height:15.75pt'><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt;min-height:15.75pt'><p class=MsoNormal>Step<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Function<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Top<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Output<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Start<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Step 1<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Step 2<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Step 3<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Step 4<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Step 5<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Step 6<o:p></o:p></p></td></tr><tr style='height:15.0pt;min-height:15pt'><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt;min-height:15pt'><p class=MsoNormal>1<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>Push (23)<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>2<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>Item added (23)<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'></td><td rowspan=5 style='border:none;border-bottom:solid black 1.0pt;padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>Stack position<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>4<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>92<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>92<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>92<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>92<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>92<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>92<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>92<o:p></o:p></p></td></tr><tr style='height:15.0pt;min-height:15pt'><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt;min-height:15pt'><p class=MsoNormal>2<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>Push (18)<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal> <o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>Item added (18)<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>3<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>75<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>75<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>18<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>18<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>75<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>75<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>75<o:p></o:p></p></td></tr><tr style='height:15.0pt;min-height:15pt'><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt;min-height:15pt'><p class=MsoNormal>3<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>Pop<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>2<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>Item removed (18)<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>2<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>23<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>23<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>23<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>23<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>23<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>23<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>23<o:p></o:p></p></td></tr><tr style='height:15.0pt;min-height:15pt'><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt;min-height:15pt'><p class=MsoNormal>4<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>Push (75)<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal> <o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal>Item added (75)<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>1<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>83<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>83<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>83<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>83<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>83<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>83<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'>83<o:p></o:p></p></td></tr><tr style='height:15.75pt;min-height:15.75pt'><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt;min-height:15.75pt'><p class=MsoNormal>5<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Push (92)<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>4<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Item added (92)<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>0<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>52<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>52<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>52<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>52<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>52<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>52<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>52<o:p></o:p></p></td></tr><tr style='height:15.75pt;min-height:15.75pt'><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt;min-height:15.75pt'><p class=MsoNormal>6<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Push (47)<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal> <o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Stack full<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td></tr><tr style='height:15.75pt;min-height:15.75pt'><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt;min-height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal>Top<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>1<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>2<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>3<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>2<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>3<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>4<o:p></o:p></p></td><td style='padding:0cm 0cm 0cm 0cm;height:15.75pt'><p class=MsoNormal align=right style='text-align:right'>4<o:p></o:p></p></td></tr></table><p class=MsoNormal><br><span style='color:#888888'>Mike Brookes <br>Semi retired gentleman from Copperfield College</span><o:p></o:p></p><div><p class=MsoNormal><br><br>On 21/04/2011 1:35 PM, Mark KELLY wrote: <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Would someone be kind enough to throw me a bone about the stack question - Q3?<br><br>I thought I knew stack implementation from my assembly language days with Z80... this question feels like walking into someone's half-finished thought process. I'm really confused about this.After half an hour of conjecture, I’ve tried four times to ask a series of sensible questions to make sense of it, and have failed every time. <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><o:p> </o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>The only apparent answer involves time travel, reversed arrays, irrelevant stack pointers and bogus bolding of stack items. The relationship between the stack and the table is only the beginning of the problem...<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><o:p> </o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I’d be delighted if anyone could walk me through this...<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><o:p> </o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Regards<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Mark<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></div><p class=MsoNormal><br>_______________________________________________<br><a href="http://www.edulists.com.au" target="_blank">http://www.edulists.com.au</a> - FAQ, Subscribe, Unsubscribe<br>IT Software Development Mailing List kindly supported by<br><a href="http://www.vcaa.vic.edu.au" target="_blank">http://www.vcaa.vic.edu.au</a> - Victorian Curriculum and Assessment Authority and<br><a href="http://www.vcaa.vic.edu.au/vce/studies/infotech/softwaredevel3-4.html" target="_blank">http://www.vcaa.vic.edu.au/vce/studies/infotech/softwaredevel3-4.html</a><br><a href="http://www.vitta.org.au" target="_blank">http://www.vitta.org.au</a> - VITTA Victorian Information Technology Teachers Association Inc<o:p></o:p></p></div><p class=MsoNormal style='margin-bottom:12.0pt'><br><br clear=all><br>-- <br>Mark Kelly<br>Manager of ICT, Reporting, IT Learning Area<br>McKinnon Secondary College<br>McKinnon Rd McKinnon 3204, Victoria, Australia<br>Direct line / Voicemail: +613 8520 9085, Fax +613 9578 9253<br><a href="mailto:kel@mckinnonsc.vic.edu.au" target="_blank">kel@mckinnonsc.vic.edu.au</a><br>VCE IT Lecture Notes: <a href="http://vceit.com" target="_blank">http://vceit.com</a><br>Moderator: IT Applications Edulist<br><br>All generalisations are false, except this one.<o:p></o:p></p></div></body></html>