Software Marathon 2011 (3 Viewers)

[MrBrightside]

Everytime i've seen them in exams at school they usually provide a subprogram containing those algorithms. I'd say as long as you know the function of each of those algorithms and considering you will be given a main program to make a sub program for if anything, so you will probably be able to just come up with one from that.

Oh and that depends on which type of sort it is.

Bubble - Yes/No?
Insertion - Yes/No?
Selection - Yes/No?

and btw my algorithm of my insertion sort, I'm desk checking it and I seem to be misinterpreting some part of it. The sort isn't making sense, because atm I have

Pass 3
Index: 1 2 3 4 5 6
Value: 18 14 2 21 7 39

As of Pass 3, and according to BOS document everything to the right of 21 should be sorted, why the fuck is 7 still there >.> - like wtf it's treating it as a bubbleSort........WTFFF IS WRONG WITH IT.

Ehhh software....The mindfuck subject.

Also whats the point of this..WHILE (Current < Last)...Current is always going to be less than Last.

 

[brent012]

Bubble - Yes/No?
Insertion - Yes/No?
Selection - Yes/No?

Actually its no for them all sorry. Selection goes through each item individually so it wouldn't have to go through to check. Bubble once again has to go through passes for each value so when the sort is completed it has to be in order, the two are essentially the same i guess but bubble doesnt just kind of search and pluck haha. Insertion sort is kind of like bubble sort, except in each pass it compares the new index against all the previously sorted stuff - so it creates a sorted part of the list rather then bubbling.

This code should make for more sense and work:

Begin InsertionSort
    For i = 1 to ArrayLength - 1
         j = i
	 while j > 0 and array[j] < array[j - 1]
	    swap(array[j],array[j - 1]
	    j = j - 1
	 EndWhile
     EndFor
End InsertionSort

Just need the same swap procedure you'd use in a bubblesort. Im not sure if its all set up for arrays starting at 0 or 1 atm, mind testing it for me lol? It would just be a matter of changing a number if not.

Oh and btw i hate some parts of software, for example these sorts are purely theory. If you made a program you would probably use a sort method built into the language which would be FAR more efficient - for eg the QuickSort.

 

[MrBrightside]

This code should make for more sense and work:

Begin InsertionSort
    For i = 1 to ArrayLength - 1
         j = i
	 while j > 0 and array[j] < array[j - 1]
	    swap(array[j],array[j - 1]
	    j = j - 1
	 EndWhile
     EndFor
End InsertionSort

Why is J set to 1 at the start? doesn't that mean it will only run once, since you decrement it.

 

[brent012]

This code should make for more sense and work:

Begin InsertionSort
    For i = 1 to ArrayLength - 1
         j = i
	 while j > 0 and array[j] < array[j - 1]
	    swap(array[j],array[j - 1]
	    j = j - 1
	 EndWhile
     EndFor
End InsertionSort

Why is J set to 1 at the start? doesn't that mean it will only run once, since you decrement it.

Haha sorry i had it = to 1 at first but it was meant to be i, it is actually i in your quote there - hard to read = S

Also made the swap part lol:

begin swap(A,B)
     Temp = A
      A = B
      B = Temp
end swap

 

[MrBrightside]

Haha sorry i had it = to 1 at first but it was meant to be i, it is actually i in your quote there - hard to read = S

Also made the swap part lol:

begin swap(A,B)
     Temp = A
      A = B
      B = Temp
end swap

But isn't that a replication of the bubblesort :/ ahaah and yeah it is i, hard to see

 

[brent012]

But isn't that a replication of the bubblesort :/ ahaah and yeah it is i, hard to see

Definitely not lol, i see why you might think that but the logic behind it is an insertion sort. But that previous example is kind of bubbling up so im not sure how they would feel about that, ill message my teacher on fb and see what he thinks.

 

[MrBrightside]

Definitely not lol, i see why you might think that but the logic behind it is an insertion sort. But that previous example is kind of bubbling up so im not sure how they would feel about that, ill message my teacher on fb and see what he thinks.

Wow that's so cool, a teacher on fb. Eh for now I'll just use the one I know, rote learning ftw! hopefully at uni they can teach it better.

Question, Explain the CPU cycle.

 

[iLazy]

The trend in the mockup appears to be more about debugging or explaining algorithms rather than writing them.

Have you guys realised that the 2011 mock-up is pretty much the same as the 2010 HSC except in the new exam format?

 

[brent012]

Wow that's so cool, a teacher on fb. Eh for now I'll just use the one I know, rote learning ftw! hopefully at uni they can teach it better.

Question, Explain the CPU cycle.

Haha yeah he is our year advisor too and we have a grade fb group. Public school as well = )

What kind of detail should we go into for that? It uses the Fetch-Decode-Execute-Store cycle. Fetch is RAM to Control unit, Decode involves the control unit, execute uses the Arithmetic Logic Unit (ALU) and store puts data back into the memory/ram. The accumulator and other registers are temporary storage inside the cpu made up of a flip-flop circuits. First data is taken from the ram and placed into the accumulator, then the ALU performs the calculation which is then stored in the accumulator and then transferred back into memory.

Have you guys realised that the 2011 mock-up is pretty much the same as the 2010 HSC except in the new exam format?

Yeah my class at school went through it and that came up

 

[harrisony]

What's different about the format?

 

[iLazy]

What's different about the format?

In section II, instead of having questions 21-23 they have questions 21-32. Questions 33 and 34 are the option topics. With this format they can test many more syllabus dot points.

 

[brent012]

What's different about the format?

Tbh they just labelled the questions differently. I thought the changes were more than they were and there was a shift to make the exams easier but there isn't. My teacher has always put the focus in exams on writing multible hard algorithms almost from scratch but in the mockup it was all debugging and just explaining/writing modules- it turns out the hsc is just far easier then all the software exams at school in general.

 

[iLazy]

Tbh they just labelled the questions differently. I thought the changes were more than they were and there was a shift to make the exams easier but there isn't. My teacher has always put the focus in exams on writing multible hard algorithms almost from scratch but in the mockup it was all debugging - it turns out the hsc is just far easier then all the software exams at school in general.

That's true! Btw did you do CSSA or Independent this year and what did you get? Also, which option topic are you doing?

 

[brent012]

That's true! Btw did you do CSSA or Independent this year and what did you get? Also, which option topic are you doing?

Im doing software developers of hardware. My teacher makes his own exams, i think quite a bit of it was the 2011 independant and cssa trials but it had stuff from other past papers afaik. I think he makes them kind of challenging after i got 2 marks off full marks in the prelim half yearly lol. Can't really compare marks because of that i guess but i got 83% in my trials - lost so many marks for copyright questions and some dodgy mc though haha.

 

[MrBrightside]

In section II, instead of having questions 21-23 they have questions 21-32. Questions 33 and 34 are the option topics. With this format they can test many more syllabus dot points.

Also gives students the opportunity to gain extra marks, as they might know several other dot points in qs 24-32 , rather than just lengthy qs on 21 to 23.

 

[MrBrightside]

Haha yeah he is our year advisor too and we have a grade fb group. Public school as well = )

What kind of detail should we go into for that? It uses the Fetch-Decode-Execute-Store cycle. Fetch is RAM to Control unit, Decode involves the control unit, execute uses the Arithmetic Logic Unit (ALU) and store puts data back into the memory/ram. The accumulator and other registers are temporary storage inside the cpu made up of a flip-flop circuits. First data is taken from the ram and placed into the accumulator, then the ALU performs the calculation which is then stored in the accumulator and then transferred back into memory.

1. Program Counter fetches the next address of the next set of code/instruction from an instruction register or RAM
2. The Control unit then decodes the bytes of data AKA Opcode and operands. Opcode is the instruction, 1st Operand is the address and (2nd operand is the name of data?)
3. Arithmetic Logic Unit executes the instruction and stores the results in the accumulator register
4. Results are then sent back to RAM

A stack register is used to keep track of the current address being processed.

^That's off the top of my head, but I'm pretty sure that's right. What is the 2nd operand? I noticed the excel book did not mention operands, but my Cambridge one did, and it said the 1st operand is the address of the code to be executed and the 2nd operand is the actual data or name (confused - it didn't mention it clearly)

 

[SpiralFlex]

Distinguish between a context diagram and a data flow diagram. (4 marks)

 

[soccer16]

Distinguish between a context diagram and a data flow diagram. (4 marks)

A context diagram represents the flow of data between systems whereas a data-flow diagram represents the flow of data between processes in a particular system.

Is that seriously a 4 marker?

 

[iLazy]

Im doing software developers of hardware. My teacher makes his own exams, i think quite a bit of it was the 2011 independant and cssa trials but it had stuff from other past papers afaik. I think he makes them kind of challenging after i got 2 marks off full marks in the prelim half yearly lol. Can't really compare marks because of that i guess but i got 83% in my trials - lost so many marks for copyright questions and some dodgy mc though haha.

Nice work in prelim actually even in your trials you beat me - I got 75%. How do you find the option topic? I lose most of my marks there, then in mc, then section II for little things like forgetting to put storage in a DFD or talking crap about a dot point I don't really know where I usually get 1/2 or 2/3.

 

[brent012]

Distinguish between a context diagram and a data flow diagram. (4 marks)

Context diagram focuses on the system as a whole including external components without consideration of how the system itself will function just showing inputs and outputs. A data flow diagram shows the flow of information between the processes in the system, external components (people) and storage.