Introduction To Data Structures — Part 2 MCQs with Explanations

Linked List is the correct answer to “Which of the following data structures can be used to implement a deque”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

LIFO is the correct answer to “What is the primary characteristic of a stack”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

O(log n) is the correct answer to “What is the average-case time complexity of binary search”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Set is the correct answer to “Which of the following data structures does not allow duplicates”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Fixed size is the correct answer to “Which of the following is a disadvantage of an array over a linked list”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Stack is the correct answer to “Which data structure is used to check for balanced parentheses in an expression”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Undo operation in text editors is the correct answer to “Which of the following is not an application of priority queue”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

public void pop() { if(q1.size()>0) { q1.poll(); } else if(q2.size()>0) { q2.poll(); } } is the correct answer to “Making the push operation costly, select the code snippet which implements the pop operation.”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Return the front element is the correct answer to “What does the following Java code do? public Object function() { if(isEmpty()) return -999; else { Object high; high = q[front]; return high; } }”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Interrupt handling is the correct answer to “What is not a disadvantage of priority scheduling in operating systems”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

A queue with insert/delete defined for both front and rear ends of the queue is the correct answer to “What is a dequeue”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

There is a Sequential entry that is one by one is the correct answer to “Entries in a stack are "ordered". What is the meaning of this statement”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

At the head of link list is the correct answer to “In linked list implementation of a queue, from where is the item deleted”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

O(1) is the correct answer to “What is the space complexity for deleting a linked list”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Single ended queue is the correct answer to “Which of the following is not the type of queue”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Delete the first element in the list is the correct answer to “What is the functionality of the following piece of code? public Object delete_key() { if(count == 0) { System.out.println("Q is empty"); System.exit(0); } else { Node cur = head.getNext(); Node dup = cur.getNext(); Object e = cur.getEle(); head.setNext(dup); count--; return e; } }”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Have fast and slow pointers with the fast pointer advancing two nodes at a time and slow pointer advancing by one node at a time is the correct answer to “Consider a small circular linked list. How to detect the presence of cycles in this list effectively”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

DCBA is the correct answer to “If the elements "A", "B", "C" and "D" are placed in a stack and are deleted one at a time, what is the order of removal”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Merge Sort is the correct answer to “Which of the following sorting algorithms can be used to sort a random linked list with minimum time complexity”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Array implementation of linked list is the correct answer to “What kind of linked list is best to answer questions like "What is the item at position n?"”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Either O(1) or O(n) is the correct answer to “What is the time complexity of inserting at the end in dynamic arrays”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Easy to delete elements in any case is the correct answer to “Which of the following is not an advantage of a priority queue”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Empty the first jar by removing it one by one from the first jar and placing it into the second jar and empty the second jar by placing all the rings into the first jar one by one is the correct answer to “You have two jars, one jar which has 10 rings and the other has none. They are placed one above the other. You want to remove the last ring in the jar. And the second jar is weak and cannot be used to store rings for a long time.”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Underflow is the correct answer to “The essential condition which is checked before deletion in a linked queue is”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

ABCD is the correct answer to “If the elements "A", "B", "C" and "D" are placed in a queue and are deleted one at a time, in what order will they be removed”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

O(m) is the correct answer to “You are asked to perform a queue operation using a stack. Assume the size of the stack is some value 'n' and there are 'm' number of variables in this stack. The time complexity of performing deQueue operation is (Using only stack operations like push and pop)(Tightly bound).”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Space Utilization and Computational Time is the correct answer to “Linked list data structure offers considerable saving in . . . . . . . .”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

5 is the correct answer to “Consider these functions: push() : push an element into the stack pop() : pop the top-of-the-stack element top() : returns the item stored in top-of-the-stack-node What will be the output after performing these sequence of operations. push(20); push(4); top(); pop(); pop(); push(5); top();”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

O(n) is the correct answer to “What is the space complexity of a linear queue having n elements”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Find and return the position of the given element in the list is the correct answer to “What is the functionality of the following piece of code? public int function(int data) { Node temp = head; int var = 0; while(temp != null) { if(temp.getData() == data) { return var; } var = var+1; temp = temp.getNext(); } return Integer.MIN_VALUE; }”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

O(1) is the correct answer to “What is the time complexity of enqueue operation”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

reverse the array is the correct answer to “What is the functionality of the following piece of Java code? Assume: 'a' is a non empty array of integers, the Stack class creates an array of specified size and provides a top pointer indicating TOS(top of stack), push and pop have normal meaning. public void some_function(int[] a) { Stack S=new Stack(a.length); int[] b=new int[a.length]; for(int i=0;i<a.length;i++) { S.push(a[i]); } for(int i=0;i<a.length;i++) { b[i]=(int)(S.pop()); } System.out.println("output :"); for(int i=0;i<b.length;i++) { System.out.println(b[i]); } }”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

public boolean empty() { return q1.isEmpty() || q2.isEmpty(); } is the correct answer to “Select the code snippet which return true if the stack is empty, false otherwise.”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

O(n) is the correct answer to “What is the time complexity to insert a node based on key in a priority queue”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

EmptyStackException is thrown is the correct answer to “What happens when you pop from an empty stack while implementing using the Stack ADT in Java”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Both O(n) and θ(n) is the correct answer to “What would be the asymptotic time complexity to add a node at the end of singly linked list, if the pointer is initially pointing to the head of the list”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Stack is the correct answer to “The data structure required to check whether an expression contains a balanced parenthesis is”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Container of objects of similar types is the correct answer to “Which of these best describes an array”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

Enqueue is the correct answer to “Given only a single array of size 10 and no other memory is available. Which of the following operation is not feasible to implement (Given only push and pop operation)”. This question is standard in competitive examination syllabi for Introduction To Data Structures.

n is the correct answer to “In the worst case, the number of comparisons needed to search a singly linked list of length n for a given element is”. This question is standard in competitive examination syllabi for Introduction To Data Structures.