What does ‘stack underflow’ refer to?
a) accessing item from an undefined stack
b) adding items to a full stack
c) removing items from an empty stack
d) index out of bounds exception
Option: c
Explanation: Removing items from an empty stack is termed as stack underflow.
What is the time complexity of pop() operation when the stack isimplemented
using an array?
a) O(1)
b) O(n)
c) O(logn)
d) O(nlogn)
Option: a
Explanation: pop() accesses only one end of the structure, and hence constant time.
)Which of the following array position will be occupied by a new element being
pushed for a stack of size N elements(capacity of stack > N).
a) S[N-1]
b) S[N]
c) S[1]
d) S[0]
Option: b
Explanation: Elements are pushed at the end, hence N.
What happens when you pop from an empty stack while implementing using the
Stack ADT in Java?
a) Undefined error
b) Compiler displays a warning
c) EmptyStackException is thrown
d) NoStackException is thrown
Option: c
Explanation: The Stack ADT throws an EmptyStackException if the stack is empty
and a pop() operation is tried on it.
Which of the following array element will return the top-of-the-stack-element for a
stack of size N elements(capacity of stack > N).
a) S[N-1]
b) S[N]
c) S[N-2]
d) S[N+1]
Option: a
Explanation: Array indexing start from 0, hence N-1 is the last index.
Which one ofthe following is an application of Stack Data Structure?
a) g function calls
b) e stock spanproblem
c) c expression evaluation
d) l the above
Option: A
The data structure required to check whether an expression contains balanced
parenthesis is?
a) Stack
b) Queue
c) Array
d) Tree
Option : a
The postfix form of A*B+C/D is?
a) *AB/CD+
b) AB*CD/+
c) A*BC+/D
d) ABCD+/*
Option : B
Which data structure is needed to convert infix notation to postfix notation?
a) Branch
b) Tree
c) Queue
d) Stack
Option : d
The prefix form of A-B/ (C * D ⋀ E) is?
a) -/*⋀ACBDE
b) -ABCD*⋀DE
c) -A/B*C⋀DE
d) -A/BC*⋀DE
Option : c
The result of evaluating the postfix expression 5, 4, 6, +, *, 4, 9, 3, /, +, * is?
a) 600
b) 350
c) 650
d) 588
Option : b
Consider the linked list implementation of a stack. Which of the following node
is considered as Top of the stack?
a) First node
b) Last node
c) Any node
d) Middle node
Option : a
Consider the following operation performed on a stack of size 5.
Push(1);
Pop();
Push(2);
Push(3);
Pop();
Push(4);
Pop();
Pop();
Push(5);
After the completion of all operation, the no of element present on stack are
a) 1
b) 2
c) 3
d) 4
Option : a
Which of the following is not an inherent application of stack?
a) Reversing a string
b) Evaluation of postfix expression
c) Implementation of recursion
d) Job scheduling
Option : d
Which of the following operation take worst case linear time in the array
implementation of stack?
a) Push
b) Pop
c) IsEmpty
d) None
Option : d
Which of the following application generally use a stack?
a) Parenthesis balancing program
b) Syntax analyzer in compiler
c) Keeping track of local variables at run time
d) All of the above
Option : d
What is the minimum number of stacks of size n required to implement a
queue of size n?
a) One
b) Two
c) Three
d) Four
Option : b
Consider the usual implementation of parentheses balancing program using
stack. What is the maximum number of parentheses that will appear on stack at
any instance of time during the analysis of ( ( ) ( ( ) ) ( ( ) ) )?
a) 1
b) 2
c) 3
d) 4
Option : c