GATE CSE
For all GATE CSE Questions
Toggle navigation
GATE Overflow
Facebook Login
Google Login
or
Email or Username
Password
Remember
Login
Register

I forgot my password
All Activity
Questions
Unanswered
Tags
Subjects
Users
Ask
Previous
Blogs
New Blog
Exams
First time here? Checkout the
FAQ
!
x
×
Close
Use the google search bar on side panel. It searches through all previous GATE/other questions.
Recent activity by rahul sharma 5
User rahul sharma 5
Wall
Recent activity
All questions
All answers
Exams Taken
All Blogs
User rahul sharma 5
Wall
Recent activity
All questions
All answers
Exams Taken
All Blogs
1
answer
1
MadeEasy Test Series
Options A) B) C) Both A and B D) None Explain...????
commented
16 hours
ago
in
Databases

27
views
databases
madeeasy_testseries
sql
relationalalgebra
0
answers
2
ME Test Series SQL
Can anyone tell why 1st is not correct? My approach:When we will join drinker and bar,we will get tuples of the drinker and the bar corresponding to his/her city.One tuple per drinker will come.Then we will join this with frequent ,the ... have one tuple,so that will be matched at max. one tuple only.And we project drinker's name. What did i miss?
asked
16 hours
ago
in
Databases

12
views
madeeasy_testseries
databases
sql
1
answer
3
turing machine
Consider the following languages: Lne={〈M〉│L(M)≠ф } Le={〈M〉│L(M)=ф } where 〈M〉 denotes encoding of a Turning machine M Then which one of the following is true? (a) Lne is r.e. but not recursive and Le is not r.e. (b) Both are not r.e. (c) Both are recursive (d) Le is r.e. but not recursive and Lne is not r.e.
commented
1 day
ago
in
Theory of Computation

34
views
theoryofcomputation
0
answers
4
Equivalence and Emptiness problems in RE
asked
1 day
ago
in
Theory of Computation

9
views
theoryofcomputation
1
answer
5
TM acceptance
commented
1 day
ago
in
Theory of Computation

52
views
1
answer
6
Doubt in GateCse Decidability Blog
asked
1 day
ago
in
Theory of Computation

23
views
decidability
theoryofcomputation
recursiverecursivelyenumerable
turingmachine
0
answers
7
Random
How to solve questions where we need to find the generated expression by the given expression . What is the techniques to solve such question ?
commented
1 day
ago
in
Theory of Computation

18
views
1
answer
8
order of leaf node in b+ tree??
answered
2 days
ago
in
Databases

26
views
dbms
b
tree
1
answer
9
Consider the following languages
commented
2 days
ago
in
Theory of Computation

842
views
turingmachine
theoryofcomputation
normal
2
answers
10
GATE1998_1.11
Regarding the power of recognition of languages, which of the following statements is false? The nondeterministic finitestate automata are equivalent to deterministic finitestate automata. Nondeterministic Pushdown automata are ... deterministic Turing machines. Multitape Turing machines are available are equivalent to Singletape Turing machines.
commented
2 days
ago
in
Theory of Computation

269
views
gate1998
theoryofcomputation
easy
1
answer
11
TOC Decidability
Are the following problems decidable? 1.{⟨M⟩∣M is a TM and there exist an input whose length is less than 100, on which M halts} I think we can simulate all the combinations of strings whose length is less than 100,and if the machine ... are not accepted by machine,Can it hang the machine?Is it also RE but NOT REC Please correct if I am going wrong
asked
2 days
ago
in
Theory of Computation

23
views
decidability
theoryofcomputation
ric
0
answers
12
TOC Rank of non terminal
S > aA A>BC B>bAd Answer given is 2.Do I need to remove useless production also for finding rank?I know we need to convert to CNF,but CNF requires to remove null production and unit production and then conver to A>BCa form.But what about useless production,if I take this production then answer is 3 else 2. Please help
asked
3 days
ago
in
Theory of Computation

11
views
contextfree
rankofnonterminal
1
answer
13
Pumping lemma for regular grammer
commented
3 days
ago
in
Theory of Computation

23
views
theoryofcomputation
lemma
pumping
pumpinglemma
1
answer
14
Rice's Theorem
I am unable to understand when to apply Rice's theorem and when to not. How L2 is decidable.
commented
3 days
ago
in
Theory of Computation

71
views
ricetheorem
decidability
theoryofcomputation
0
answers
15
Rice theorem Clarification
I need to understand when to apply RICE's theorem and when to not. Questions like: Turing machine makes at least five moves,It accepts a string input of length atleast five ,TM halts for every input on length <50 are all ... will say yes and some will say NO.Then why can't we use same concept on above metioned questions? Please help
commented
3 days
ago
in
Theory of Computation

25
views
theoryofcomputation
ricetheorem
decidability
0
answers
16
[TOC] Reduction theorem
If P1<=P2 means P1 is reducible to p2,then which is true? 1, If P1 is RE But Not REC,P2 is also RE but not REC? 2. If P2 is RE But Not REC,P1 is also RE but not REC? As per my ... Please help Edit: As a part of this solution please tell me,whether undecidable includes semidecidable also?And whether semidecidable includes decidable also?
edited
3 days
ago
in
Theory of Computation

20
views
theoryofcomputation
decidability
1
answer
17
TOC Finite automata
If n state finite automata accespts infinite language then what is the length of min, and max. cycle?
commented
3 days
ago
in
Theory of Computation

49
views
theoryofcomputation
finiteautomata
dfa
0
answers
18
[TOC] CNF Tree Depth
1. Assume that we have CNF tree of depth of h(Assume root at height 0).What is the maximum yeild possible in terms of h? 2. Assume that we have a string of length n,what is the min and max height of parse tree possible in CNF. Please explain
asked
4 days
ago
in
Theory of Computation

8
views
theoryofcomputation
contextfree
cnf
derivationtree
1
answer
19
DCFl Decidability
Under what operations DCFL is Not decidable?I
commented
4 days
ago
in
Theory of Computation

30
views
decidability
1
answer
20
[TOC] Finite automata Infinite language
commented
4 days
ago
in
Theory of Computation

30
views
theoryofcomputation
finiteautomata
dfa
0
answers
21
Decidability in CFG
As we know that equivalence in CSL is undecidable,so if i want to look for Nonequivalence,then will it be complement of this and answer will be NOT RE or will it be RE BUT NOT REC. Similarly for disjointness test,if i say i want to see if some string is common in two CFG,will it be RE BUT NOT REC or NOT RE
commented
4 days
ago
in
Theory of Computation

18
views
theoryofcomputation
decidability
0
answers
22
TOC Pumping Lemma
In pumping lemma it says if there is a string whose length is >=N,where N is number of states in dfa,then language of machine is infinite,but there is one upper constraing also. 2N1>=W>=N Can anyone tell me about the use of 2N1 here ?
commented
5 days
ago
in
Theory of Computation

19
views
theoryofcomputation
pumpinglemma
pumping
lemma
0
answers
23
TOC Grammers equivalence
Are the following two grammers equivalent? G1 :S> aS  e G2: S> aaS  e I was reading this question somewhere and it was written that second one is sentential form of first and they are equal,but i dont think so.Second one will generate only even a's but first one is generating every combination of a.Please help
asked
5 days
ago
in
Theory of Computation

18
views
theoryofcomputation
0
answers
24
[DBMS]ME Test Series Schedule Classification
asked
6 days
ago
in
Databases

13
views
madeeasy_testseries
databases
0
answers
25
Made Easy Test Series DBMS[SQL]
commented
6 days
ago
in
Databases

52
views
databases
madeeasy_testseries
1
answer
26
HamacherDMA
The average seek time and rotational delay in a disk system are 6ms and 3ms, respectively. The rate of data transfer to or from the disk is 30 Mbytes/sec and all disk accesses are for 8 Kbytes of data. Disk DMA controller, the ... a disk unit, on average over a long period of time during which a sequence of independent 8Kbyte transfers takes place?
commented
6 days
ago
in
CO & Architecture

334
views
co&architecture
dma
1
answer
27
Directed acyclic graph
In questions like, when asked to find the edges or nodes in the DAG of following expression, a=a+b*c(a+b)+(b*c) do we also consider "=" as a node and its related edges?
answered
6 days
ago
in
Compiler Design

36
views
compilerdesign
0
answers
28
Made Easy
The average seek time and rotational delay in a disk system are 6ms and 3ms respectiely. The rate of data transfer to or from the disk is 30 MBps and all disk accesses are of 8 KB. Disk DMA controller, the processor, and the main ... .How many disk units are there that can be simultaneously transferring data to or from the main memory? Correct option given: 13
commented
6 days
ago
in
CO & Architecture

53
views
madeeasy_testseries
co&architecture
0
answers
29
Made Easy demo test
4 word instruction will take 4 memory refrences or 3 memory refrences ?
commented
6 days
ago
in
CO & Architecture

22
views
#computerorganisationandarchitecture
3
answers
30
GATE2007IT66
Consider the following two transactions : T1 and T2. T1 : read (A); T2 : read (B); read (B); read (A); if A = 0 then B ← B + 1; if B ≠ 0 then A ← A  1; write (B); write (A); Which of the following schemes, using shared and exclusive locks, ... B + 1; then A ← A  1; write (B); write (A); unlock (A); unlock (A); unlock (B); unlock (B); commit; commit;
commented
Jan 9
in
Databases

577
views
gate2007it
databases
transactions
normal
0
answers
31
DBMS Number of Serializable schedules
commented
Jan 9
in
Databases

27
views
databases
conflict_serializable
view_serializable
2
answers
32
Maths : what is 4 mod 2
a mod n : tell the formula ?
commented
Jan 9
in
Mathematical Logic

54
views
1
answer
33
BCNF Decomposition
commented
Jan 8
in
Databases

45
views
databasenormalization
databases
functionaldependencies
bcnfdecomposition
1
answer
34
[DBMS] Time stamp Ordering Protocol
commented
Jan 8
in
Databases

69
views
databases
2
answers
35
GateBook: DBMS: View/Conflict Serializable Schedules
commented
Jan 8
in
Databases

366
views
transactions
conflict_serializable
databases
view_serializable
1
answer
36
Avl vs btree
I know advantages of btree. But after reading that I want to ask in what aspect Avl trees are useful over b tree? Give some example please.
commented
Jan 8
in
Databases

29
views
databases
btree
2
answers
37
[DBMS Schedules] Lost update vs ww conflict
commented
Jan 7
in
Databases

47
views
databases
transactions
conflict_serializable
2
answers
38
OS DOubt
answered
Jan 6
in
Operating System

44
views
1
answer
39
[DBMS] Position of Nulls using order by clause
asked
Jan 6
in
Databases

43
views
sql
databases
2
answers
40
[Compiler Design] Find number of reductions
commented
Jan 6
in
Compiler Design

96
views
compilerdesign
18,813
questions
23,785
answers
51,449
comments
20,130
users