What is the time complexity to count the number of elements in the linked list?
a) O(1)
b) O(n)
c) O(logn)
d) O(n2)
Explanation: To count the number of elements, you have to traverse through the entire list, hence complexity is O(n).
How do you calculate the pointer difference in a memory efficient double linked list?
a) head xor tail
b) pointer to previous node xor pointer to next node
c) pointer to previous node – pointer to next node
d) pointer to next node – pointer to previous node
Explanation: The pointer difference is calculated by taking XOR of pointer to previous node and pointer to the next node.
What is the worst case time complexity of inserting a node in a doubly linked list?
a) O(nlogn)
b) O(logn)
c) O(n)
d) O(1)
Explanation: In the worst case, the position to be inserted maybe at the end of the list, hence you have to traverse through the entire list to get to the correct position, hence O(n).
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
Explanation: Removing items from an empty stack is termed as stack underflow.
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]
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
Explanation: The Stack ADT throws an EmptyStackException if the stack is empty and a pop() operation is tried on it.
