Question 1
A problem in NP is NP-complete if
It can be reduced to the 3-SAT problem in polynomial time
The 3-SAT problem can be reduced to it in polynomial time
It can be reduced to any other problem in NP in polynomial time
Some problem in NP can be reduced to it in polynomial time
Question 2
Language L1 is polynomial time reducible to language L2. Language L3 is polynomial time reducible to L2, which in turn is polynomial time reducible to language L4. Which of the following is/are True?
I. If L4 ∈ P, L2 ∈ P
II. If L1 ∈ P or L3 ∈ P, then L2 ∈ P
III. L1 ∈ P, if and only if L3 ∈ P
IV. If L4 ∈ P, then L1 ∈ P and L3 ∈ P
II only
III only
I and IV only
I only
Question 3
Which of the following is an NP-hard problem that can be approximated using a greedy algorithm?
Set cover problem
Traveling salesman problem
Knapsack problem
Minimum spanning tree problem
Question 4
Assuming P != NP, which of the following is true ?
(A) NP-complete = NP
(B) NP-complete [Tex]\\cap [/Tex]P = [Tex]\\Phi [/Tex]
(C) NP-hard = NP
(D) P = NP-complete
A
B
C
D
Question 5
Question 6
Let SHAM3 be the problem of finding a Hamiltonian cycle in a graph G = (V,E) with V divisible by 3 and DHAM3 be the problem of determining if a Hamiltonian cycle exists in such graphs. Which one of the following is true?
Both DHAM3 and SHAM3 are NP-hard
SHAM3 is NP-hard, but DHAM3 is not
DHAM3 is NP-hard, but SHAM3 is not
Neither DHAM3 nor SHAM3 is NP-hard
Question 7
Consider the following two problems of graph. 1) Given a graph, find if the graph has a cycle that visits every vertex exactly once except the first visited vertex which must be visited again to complete the cycle. 2) Given a graph, find if the graph has a cycle that visits every edge exactly once. Which of the following is true about above two problems.
Question 8
Given the following statements: S1 : Every context-sensitive language L is recursive S2 : There exists a recursive language that is not context-sensitive Which statements are true?
Only S1 is correct
Only S2 is correct
Both S1 and S2 are not correct
Both S1 and S2 are correct
Question 9
The problems 3-SAT and 2-SAT are
Both NP-complete
Both in P
NP-complete and in P, respectively
Undecidable and NP-complete, respectively
Question 10
For problems X and Y, Y is NP-complete and X reduces to Y in polynomial time. Which of the following is TRUE?
If X can be solved in polynomial time, then so can Y
X is NP-complete
X is NP-hard
X is in NP, but not necessarily NP-complete
There are 20 questions to complete.