What it is to crack GATE Exam? Part - IV.

1) Mock tests.
-> This should be started 1 month before the exam. Mock tests are very important to analyze how you are performing with respect to time, tension etc. Make sure to do create an exam environment, set time, isolate yourself from day to day disturbances, and take the exam. You can find mock paper @GateForum.com. Analyze your answers with the key, collect all the questions you have answered wrongly, classify them to following categories

1. Don't have a clue of the question.
2. I have read something like this, but not sure what is the answer.
3. I have read this kind of question, but forgot who to do it due to tension.
   
4. Solved the problem, but wrong answer as i have missed some parameters in the question.
5. Solved the problem, marked it wrongly.
6. Out of syllabus/wrong key/partial question (Ignore these questions)
   

Now out of above 4 should be fixed by reading the question completely before jumping to answer it. 5 can be fixed by cross checking every answer if that is the one i want to mark(Question number as well as the choice). (Clarification: Assume it take extra 5 on avg seconds per question, 72*5 = 7 mins out of whole time, which is not very bad if you can save 5-6 questions that come into this category).

For 1,2,3 the reason for not answering is that you are not very confident on those topics, divides all the questions in this bucket into various sub topics. Once you are done with this you, I will bet that you will be surprised to see the wrongly answered questions will go to well defined subtopics in some or the other subjects. Bingo!! You found what need to do now i guess, prepare these topics and Repeat the same with few more mock tests.

2) Last minute preparation.
On the day just before just browse important formulas, constants, TODO stuff, Do a mock in the afternoon, analyze again, ideally if you have done the mock tests prep as i have mentioned in the last question, you will get good score and feel lot confident in the previous night, and Next day is the day you come out the examination center and shout i have made it. Hurray......

All the best for all the Gate Aspirants.......

Satya

What it is to crack GATE Exam? Part - III.

1) What are you going to be tested for in Gate Exam?

-> I have already briefed this in the first post, let me elaborate on this in this post. Gate exam tries to test the "Concepts of Engineering". For computer science, let me present how to look at things with few examples . (I might not explain in deep here, but give a glimpse on how to look at things)

Questions: (each question can have multiple answers)

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a) Computation Theory: You can represent a regular language using

i) Finite Automata

ii) Push down Automata

iii) Linear Bounded Automata

iv) Turing Machine

b) Data Structures: Which of the following is/are true.

i) Binary tree and Binary search tree means the same.

ii) A complete binary tree is not balanced.

iii) Worst Complexity of finding a element is a binary search tree is Theta(log(n)).

c) Computer Architecture: Let's take as an example a system with 512 KB of L2 cache and 64 MB of main memory. Assuming cache is 4 way associative, (memory operations are of word length - typically 32 bytes), It uses LRU for eviction policy.

1) The cache has 512K address lines. (True/False)

2) Assuming the two consecutive memory requests are random, what is the probability that the second request will evict the data of the first request from the cache is (<0.5>0.5 or =0.5).

Answers:

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a) If your answer is (i), wow great you are right, but since there can be multiple answers as i said, all (i), (ii), (iii), (iv) are correct. Can you answer why?

So there are four types of languages as you might have read in your books.

Type 1: Unrestricted grammar, some formulae, can be represented using turing machine,

Type 2: and so on.

But we should know is that as we go to higher types they get more and more restricted, ie type 2 languages are subset of type 1, type 3 is subset of type 2, so on.

That means, type 4 grammar is subset of all other types, which is type 4 can be represented using any automaton that is used for representing type 1, type 2, type 3 and type 4. Hence the answer.

b) Lets just about understanding the the data structure means.

i) False. Refer to definitions.

ii) False. A complete binary tree is a balanced tree, Again refer to definitions.

iii) False. Average case complexity is Theta(log(n)), Worst case complexity is O(n). and best case complexity Omega(1). Again if you understand the terms Theta, Big O, Omega, then you can appreciate this question, and only then you will understand why.

c) i) False, since the size of each cache line is word length as that is unit of memory operation, it can't fetch data in smaller sizes, so number of cache lines will be 512K/32 = 16K cache lines.

Refer this link to understand what is 4 way associative memory.

ii) Answer is 0. Since in a four way associative memory, that uses LRU, there still 3 other cache lines that the second request can go to. If if the other 3 cache lines are filled, it will evict of these 3 as, it is LRU policy.

(You can understand these explanation only once you understand the 3 types of caches)

I know that i have not 100% clearly explained the answers, i want you to explore it. I have given a glimpse of how think, and approach.

So if you start reasoning while preparing for the Gate exam, I am sure u have mastered the technical part of cracking the gate exam. Last part is how to allocate time and prepare for the exam, is in part IV