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D1 (Decision 1) 17 May 2013 Official Thread

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Reply 260
i am preparing to absolutely ace D1 and hopefully get high 90's ums, think it will make up for the 30 ill probbably get in c2!!
Original post by Jammy4410
what is the order of difficulty of the chapters of this book?


My personal opinion (from easiest to hardest):
7) Matchings
1) Algorithms
3) Algorithms on Networks
2) Graphs and Networks
4) Route Inspection
5) Critical Path Analysis
6) Linear Programming
Reply 262
Original post by Season One
If i don't get an A this time i think i will use prims algorithm to find the shortest route to the nearest tall building then jump off it.


That is actually hilarious.

Anyway please can someone help me!!!!

When you do Integer Solutions for Linear Programming how do you know whether or note your answer is in the feasible region?

Please see my work this is May 2012. Pardon my Handwriting, I tried to do it in 1hr 15 Mins, to put myself under Exam Style Pressure.

I don't know how to choose which Integers or rather Test which one is the correct Maximum

I got this wrong twice now.

IMG-20130514-00854.jpg
Original post by Better
That is actually hilarious.

Anyway please can someone help me!!!!

When you do Integer Solutions for Linear Programming how do you know whether or note your answer is in the feasible region?

Please see my work this is May 2012. Pardon my Handwriting, I tried to do it in 1hr 15 Mins, to put myself under Exam Style Pressure.

I don't know how to choose which Integers or rather Test which one is the correct Maximum

I got this wrong twice now.

IMG-20130514-00854.jpg


do you have a copy of the graph?
Reply 264
Original post by calla_lily
do you have a copy of the graph?



http://www.tomred.org/uploads/7/7/8/3/778329/d1_ms_june_2012.pdf

Page 13.

My graph is pretty identical to this one. I can upload it though if you need it to help me out.
Original post by Better
Yeah mate, I'll hit you up on your wall, thanks to the studentroom loads of people are helping me so I'm past paper ready for C3 C4, not D1 yet


How are you getting help?
Reply 266
Okay the book says:

"Evaluate the objective function, and most importantly, check that the integer solutions lie in the feasible region,

*Then they check their integers with EVERY CONTRAINT* "

Isn't there a faster way to check? That would take long, to check 4 Co-ordinates (or 8 Values) against 4/5 Inequalities.

So so glad I made that mistake now. Phew! I won't make that mistake on Friday!!!
Reply 267
Original post by Brunette_Gem
How are you getting help?


I can't even remember making that post. People give tips and help.

If it wasn't for this Forum my D1 would be looking bad, but I've been here getting tips for like 2 weeks now.

There are teachers who recommend videos to watch, and give you advice based on past students.

Exam Technique is crucial.
Just found out you have to "change status" for matching questions -___- *face-palm*

How did I not know this, so I guess this is where all my accuracy marks went for the matchings questions in the Jan exam :tongue:
ImageUploadedByStudent Room1368562103.848938.jpgImageUploadedByStudent Room1368562159.963755.jpg

Hello I was wondering if you guys could tell me if this scheduling diagram is right?? Ignore the crappy shading and the other boxes 😳


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Original post by Flounder1
ImageUploadedByStudent Room1368562103.848938.jpgImageUploadedByStudent Room1368562159.963755.jpg

Hello I was wondering if you guys could tell me if this scheduling diagram is right?? Ignore the crappy shading and the other boxes 😳


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Its perfect because you have not broken any dependencies , so your answer is correct
ImageUploadedByStudent Room1368562742.366565.jpg
Sorry again question e and f are confusing I don't know how to complete e without a gang chart T_T is their a way you can do it without making one?


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Original post by Flounder1
ImageUploadedByStudent Room1368562742.366565.jpg
Sorry again question e and f are confusing I don't know how to complete e without a gang chart T_T is their a way you can do it without making one?


Posted from TSR Mobile


is it okay if you could zoom it a bit , its quite blurry . thanks
Guys,

You know sometimes after you complete a Dijkstra algorithm and state the quickest route's length.... there's usually another question saying state the shortest route and length if you could not go through letter "X", how do you guys go about doing this ? :smile:
Do you just use your own initiative, or is there some kind of algorithm/ technique that is typically use. I believe its 2 marks and none are allocated to the working out, not too sure :smile:

Thanks in advance as always !
ImageUploadedByStudent Room1368563136.016516.jpgImageUploadedByStudent Room1368563188.087610.jpg
Sorry here it is again e and f


Posted from TSR Mobile
Original post by Flounder1
ImageUploadedByStudent Room1368563136.016516.jpgImageUploadedByStudent Room1368563188.087610.jpg
Sorry here it is again e and f


Posted from TSR Mobile


okay for the activities to be happening at day 20 is the answer D, I , J , L ?
Reply 276
guys how do i get the Jan 2013 paper???
Original post by posthumus
Guys,

You know sometimes after you complete a Dijkstra algorithm and state the quickest route's length.... there's usually another question saying state the shortest route and length if you could not go through letter "X", how do you guys go about doing this ? :smile:
Do you just use your own initiative, or is there some kind of algorithm/ technique that is typically use. I believe its 2 marks and none are allocated to the working out, not too sure :smile:

Thanks in advance as always !


What I do, is that , I see which alternative path gives the lowest value, so I chose the second lowest value and go from there, its really trial and error, you have to play around with your calculator with the routes to see which value gives you the lowest
Original post by alex011
guys how do i get the Jan 2013 paper???


here you go :smile:

http://www.studentforums.biz/

the paper and mark scheme is found on this site
So any revision tips? I just keep making the most silliest mistakes anyone know how to conquer that? e.g. mistakes in bubble sort like missing a number or not having the final pass or something like that.

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