<p>FRQs are released at 4:00...anyone care to discuss?</p>
<p>bump!!!!!!!!!!!!!!!!!!</p>
<p>Maybe?</p>
<p>I didn't think they were that hard.</p>
<p>What was your answer to #1(a).??? The self-divisor problem??? My solution was incredibly long (longer than I though AP usually called for)</p>
<p>I first determined the digits in the number.
Then generated an array of the digits.
Checked the number divided by each divisor to ensure divisibility.</p>
<p>I did the same smder. For part c and d for question 1, was the answer n^3?</p>
<p>What??? Im sorry...AP Computer Science A</p>
<p>There was no part C and D....</p>
<p>For AB, sorry about that, guess I had the questions mixed up.</p>
<p>For part c), O(n^2), and for part d) O(n).</p>
<p>And there was no self divisor problem on the AB exam, what did you mean by that?</p>
<p>I meant the A exam</p>
<p>I thought that both part c) and d) were O(n^2) because in both you had to go through the elements twice? Once to add it to the list, and then another time in the loop.</p>
<p>Or am I totally wrong here?</p>
<p>For part C I got O(n-squared) because you have to loop through each element in the ArrayList, an O(n) operation, and for each element, copy it's content into the array, an O(1) operation, and call the remove method for the ArrayList - another O(n) operation because it shifts all of the elements in the list down. So it's O(n) * ( O(n) + O(1) ) = O(n-squared).</p>
<p>The second one, however, I got O(n). You loop through the whole ArrayList an O(n) operation. Then you copy the chosen value into the array, an O(1) operation. Then you switch the chosen index in the ArrayList with the last index , another O(1) operation, and finally remove the last element O(1).</p>
<p>O(n) * ( O(1) + O(1) + O(1) ) = O(n)</p>
<p>yeah, that's wrong, but it was a tricky question. Since it added the elements to the list, then ran the loop, it was actually O(n + n), which equals O(2n). Since coeficiants aren't included in big-Oh notation, the second one was O(n). If it had added the elements within the loop, it would have been O(n^2). The first one was O(n^2) because the remove method, which was inside the loop runs in O(n) time. Therefore, it evaluated to O(n^2 + n) which simplifies to O(n^2).</p>
<p>Edit: mvalestein, I think you got the right answer, but the wrong reasoning. The first one was O(n^2) because of the loop and the remove. Only the largest big-Oh aspect is considered. The second one was O(n) because the loop was O(n) and the remove was O(1). The adding the elements to the array had nothing to do with the problem.</p>
<p>CS A Exam:</p>
<p>for #1(a) I converted to a string, used charat(i) in a for loop for each digit, converted back to an int, and checked for divisibility
must have been 3 or 4 lines max</p>
<p>however, I cast a char into an int (wouldn't actually work) instead of using parseInt() or whatever the hell you're supposed to do. how much do you think i'll get off for that?</p>
<p>Oh, I know they wouldn't have affected the run-time, I just put them in there because they were part of the algorithm that CB gave in the question.</p>
<p>Are we allowed to use methods not shown in the appendix like parseInt ?
For the isSelfDivider code, I did division by the decimal place like:
2435/1000= 2
2435-2000=435
435/100= 4
435-400=35
35/10= 3
35-30= 5</p>
<p>I hope my solution is understandable, it took me like 8 minutes to think of it, I didn't want to do substring. </p>
<p>For the other part, returning an array of the first n self Dividers starting from a
I didn't realize we had the array size (n, duh) so I proceeded to making an ArrayList, and then converting it into an int array. I wonder if I will get less points because of that?</p>
<p>The game one was the most provoking for me. I didn't think it was very well clearly documented, but things started making sense like 2 minutes before time was called. I think I did alright.</p>
<p>I converted it to string initially for #1, but then since I had like 40 minutes left I just sat there and spent like 10 minutes coming up with the right way. I think I first counted the number of integers in the number. Then I did divided the number by the 10^(i) power and used the %.
I hope my logic wasn't wrong...</p>
<p>I also didn't like the 4th question, it was weird</p>
<p>Eek! (int)x.charAt(i) doesn't work? That can't be good. I was banking on a good free response score (I got a perfect on the 2004 exam I took as practice and it barely scraped me a 5 due to my abysmal multiple choice performance).</p>
<p>This year's free response was so much harder. >.<</p>
<p>so i didn't even bother learning the case study, and left all of those blank except 2 that i think i got on the MC and partial credit for part A on the FRQ one...
how much will that hurt me?</p>
<p>yea i didn't bother to learn it either, so i skipped like 2 of the mbs multiple choice and i didnt get to/write anything on the mbs free response </p>
<p>how lenient is the curve usually? i'm hoping a 5 isn't out of the question because of this</p>
<p>oh, and i'm talking about the AB</p>