example of a logic bug using pseudocode
popeyerayaz
The question is as follows:
9. Present an example of a logic bug using pseudocode and explain your
answer. (10 points)
Temperature = 70
if (Temperature >69) and (Temperature < 100 )
THEN
openWindows;
Will work because if temperature is higher than 69 degrees and
temperature is lower than 100 degrees windows will open.
2. Gentlemen, after reading your advise I had run the code in C++,
then stated it back in pseudocode. I suppose the programmer could
mistakenly use the "AND" && operator instead of the "OR" || operator
which I found the latter to run a loop which I couldn't end, not even
with a ctrl-c, and had to push the power button in to turn off my
computer (please keep that in mind). Also found that the temperatures
reflected would better reflect opening the windows and not closing
them.
Temperature = 70
if (Temperature >69) and (Temperature < 100 )
THEN
openWindows;
Will work because if temperature is higher than 69 degrees and
temperature is lower than 100 degrees windows will open.
The code generated: numbered list 70-99
------------------------------------------------------------------------------------------------------------------------------------------------------
Temperature = 70
if (Temperature >69) or (Temperature < 100 )
THEN
openWindows;
Won't work because windows will stay closed due to temperature will
always be under 100 degrees the fault lies with the "or" "||" operator
which was used instead of the "and" (&&) operator.
The code generated: an infinite loop of never ending numbers that
crashed my computer.
Thank You,
Ray The code generated: numbered list
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Temperature = 70
if (Temperature >69) or (Temperature < 100 )
THEN
openWindows;
Won't work because windows will stay closed due to temperature will
always be under 100 degrees the fault lies with the "or" "||" operator
which was used instead of the "and" (&&) operator.
The code generated: an infinite loop of never ending numbers that
crashed my computer.
Thank You,
Ray
Richard Heathfield
<snip>
> I suppose the programmer could
> mistakenly use the "AND" && operator instead of the "OR" || operator
> which I found the latter to run a loop which I couldn't end, not even
> with a ctrl-c, and had to push the power button in to turn off my
> computer (please keep that in mind).
Modern multi-tasking computer systems generally provide some way to
terminate a process from outside the process itself. For example, on
Windows you could have brought up the Task Manager (Ctrl-Alt-Del
nowadays), identified the process, selected it, and terminated it. Under
Linux, you could have used ps -eaf | grep <taskname> to find the task's
process ID (pid) and then used kill -9 <pid> to terminate the task.
--
Richard Heathfield <http://www.cpax.org.uk>
Email: -http://www. +rjh@
Google users: <http://www.cpax.org.uk/prg/writings/googly.php>
"Usenet is a strange place" - dmr 29 July 1999
Nick Keighley
your post is very confusing
> I want run this by the group for correctness.
> The question is as follows:
>
> 9. Present an example of a logic bug using pseudocode and explain your
> answer. (10 points)
>
> Temperature = 70
> if (Temperature >69) and (Temperature < 100 )
> THEN
> openWindows;
else
openLinux
:-)
> Will work because if temperature is higher than 69 degrees and
> temperature is lower than 100 degrees windows will open.
> 2. Gentlemen, after reading your advise [advice?] I had run the code in C++,
what gentlemen? what advice?
> then stated it back in pseudocode. I suppose the programmer could
> mistakenly use the "AND" && operator instead of the "OR" || operator
> which I found the latter to run a loop which I couldn't end,
how the hell can the above p-code loop??!
> not even
> with a ctrl-c, and had to push the power button in to turn off my
> computer (please keep that in mind).
I think you need a new computer.
> Also found that the temperatures
> reflected would better reflect opening the windows and not closing
> them.
what does "temperature reflected" mean? The code you've posted
doesn't close windows.
> Temperature = 70
> if (Temperature >69) and (Temperature < 100 )
> THEN
> openWindows;
> Will work because if temperature is higher than 69 degrees and
> temperature is lower than 100 degrees windows will open.
why did you post this twice?
> The code generated: numbered list 70-99
what?
> ------------------------------------------------------------------------------------------------------------------------------------------------------
>
> Temperature = 70
> if (Temperature >69) or (Temperature < 100 )
> THEN
> openWindows;
>
> Won't work because windows will stay closed due to temperature will
> always be under 100 degrees the fault lies with the "or" "||" operator
> which was used instead of the "and" (&&) operator.
> The code generated: an infinite loop of never ending numbers that
> crashed my computer.
there is no loop in the above code
> Thank You,
>
> Ray The code generated: numbered list
>
> ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
>
> Temperature = 70
> if (Temperature >69) or (Temperature < 100 )
> THEN
> openWindows;
>
> Won't work because windows will stay closed due to temperature will
> always be under 100 degrees the fault lies with the "or" "||" operator
> which was used instead of the "and" (&&) operator.
> The code generated: an infinite loop of never ending numbers that
> crashed my computer.
>
> Thank You,
>
> Ray
why did you post this twice?
--
Nick Keighley
Richard
Is the sole reason for your reply to be rude, obnoxious and generally
show off? If so, well done. 10/10.
Kenny McCormack
Richard <rgr...@gmail.com> responded to that jerky Nick Keighley
<nick_keigh...@hotmail.com> thusly:
...
>Is the sole reason for your reply to be rude, obnoxious and generally
>show off? If so, well done. 10/10.
Of course it is. Is there (quite seriously) any other reason to post to
clc?
(And you should have seen the smile on his face when he did it...)
rahul
<snip>
You aren't making much sense. Please re-phrase your question in a way
that everyone can understand it. And try posting to the point.
Nick Keighley
oh course. :-)
if he wants help (I assume that's why he posted to comp.lang.c)
then he's going to have to ask a clear question. His post seemed
to be part of a longer converstation or had been extracted from
another post. I found it unclear. Perhaps if he asked a clear
question he'd get better help. Improving his ability to ask
questions might even make him a better programmer.
What was your reason for posting?
--
Nick Keighley
When it comes to feeding trolls, taking offense at their posts is
like serving them Lobster Thermidor aux Crevettes with Mornay sauce
served in a Provencale manner with shallots and aubergines garnished
with truffle pate, brandy and with a fried egg on top and Spam.
vipp...@gmail.com
wrote:
<snip reply to troll>
> What was your reason for posting?
Trolling.
> When it comes to feeding trolls, taking offense at their posts is
> like serving them Lobster Thermidor aux Crevettes with Mornay sauce
> served in a Provencale manner with shallots and aubergines garnished
> with truffle pate, brandy and with a fried egg on top and Spam.
s/taking offense/replying