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This quiz contains MCQs on PDA acceptance by final state and empty stack, conversions from PDA to grammar and grammar to PDA or DPDA, DPDA with regular or context-free languages, and ambiguous grammar.
Which of the operations are eligible in PDA?
Push
Delete
Insert
Add
The class of languages not accepted by non-deterministic, nonerasing stack automata is
NSPACE(n2)
NL
CSL
All of the above
A string is accepted by a PDA when
The stack is not empty
It is in the acceptance state
All of the above
None of the above
The following move of a PDA is based on the
Present state
Input symbol
Present state and input symbol
None of the above
Let T= {p, q, r, s, t}. The number of strings in S* of length four such that no symbols can be repeated is
120
625
360
36
Which of the following relates to Chomsky hierarchy?
Regular
CFL
CSL
None of the above
Which of the following is an incorrect regular expression identity?
R+f=R
eR=e
Rf=f
None of the above
Which of the following regular expressions allows strings on {a,b}* with length n, where n is a multiple of 4?
(a+b+ab+ba+aa+bb+aba+bab+abab+baba)*
(bbbb+aaaa)*
((a+b)(a+b)(a+b)(a+b))*
None of the above
Which of the following strings do not belong to the regular expression (a)*(a+cba)?
*(a+cba)a) aa
aaa
acba
acbacba
A non-deterministic two way, nested stack automaton has an n-tuple definition. What is the value of n?
5
8
4
10
Which of the following is a push-down automaton with only a symbol allowed on the stack along with the fixed symbol?
Embedded PDA
Nested stack automata
DPDA
Counter automaton
A pushdown automaton accepts a language if it is
Regular
Context-free
Regular and context-free
None of the above
Which of the following strings is not generated by the grammar S->SaSbS|e?
aabb
abab
abaabb
None of the above
Which of the following is analogous to NFA and NPDA?
Regular language and context-free language
Regular language and context-sensitive language
Context-free language and context-sensitive language
None of the above
Pushdown automata accept __ languages.
Type 3
Type 2
Type 1
Type 0
