These Heap (Data Structure) MCQs contain questions and answers on heap, binary and weak heap, binomial and fibonacci heap, d ary heap, ternary heap, pairing and leftlist heap, skew heap, min and max heap. We have the best collection of Heap (Data Structure) MCQs and answer with FREE PDF. These Heap (Data Structure) MCQs will help you to prepare for any competitive exams like: BCA, MCA, GATE, GRE, IES, PSC, UGC NET, DOEACC Exams at all levels – you just have to practice regularly.

**1. For construction of a binary heap with property that parent node has value less than child node. In reference to that which line is incorrect. Line indexed from 1.**

```
1. add(int k)
2. {
3. heap_size++;
4. int i = heap_size - 1;
5. harr[i] = k;
6. while (i != 0 && harr[parent(i)] < harr[i])
7. {
8. swap(&harr[i], &harr[parent(i)]);
9. i = parent(i);
10. }
11. }
```

a) Line – 3

b) Line – 5

c) Line – 6

d) Line – 7

**Answer: **Line – 6

**2. What is the best case complexity in building a heap?**

a) O(nlogn)

b) O(n2)

c) O(n*longn *logn)

d) O(n)

**Answer: **O(n)

**3. Given an array of element 5, 7, 9, 1, 3, 10, 8, 4. Which of the following are the correct sequences of elements after inserting all the elements in a min-heap?**

a) 1,3,4,5,7,8,9,10

b) 1,4,3,9,8,5,7,10

c) 1,3,4,5,8,7,9,10

d) 1,3,7,4,8,5,9,10

**Answer: **1,3,4,5,7,8,9,10

**4. State the complexity of algorithm given below.**

```
int function(vector<int> arr)
int len=arr.length();
if(len==0)
return;
temp=arr[len-1];
arr.pop_back();
return temp;
```

a) o(n)

b) O(logn)

c) O(1)

d) O(n logn)

**Answer: **O(n logn)

**5. What is the location of a parent node for any arbitary node i?**

a) (i/2) position

b) (i+1)/ position

c) floor(i/2) position

d) ceil(i/2) position

**Answer: **floor(i/2) position

**6. Given the code, choose the correct option that is consistent with the code. (Here A is the heap)**

```
build(A,i)
left-> 2*i
right->2*i +1
temp- > i
if(left<= heap_length[A] ans A[left] >A[temp])
temp -> left
if (right = heap_length[A] and A[right] > A[temp])
temp->right
if temp!= i
swap(A[i],A[temp])
build(A,temp)
```

a) It is the build function of max heap

b) It is the build function of min heap

c) It is general build function of any heap

d) It is used to search element in any heap

**Answer: **It is the build function of max heap

**7. What is the space complexity of searching in a heap?**

a) O(logn)

b) O(n)

c) O(1)

d) O(nlogn)

**Answer: **O(n)

**8. Which of these operations have same complexities?**

a) Insertion, find_min

b) Find_min, union

c) Union, Insertion

d) Deletion, Find _max

**Answer: **Union, Insertion

**9. The Statement “Fibonacci heap has better amortized running time in compare to a binomial heap”.**

a) True

b) False

**Answer: **True

**10. Given a heap of n nodes. The maximum number of tree for building the heap is.**

a) n

b) n-1

c) n/2

d) logn

**Answer: **n

**11. Choose the option with function having same complexity for a fibonacci heap.**

a) Insertion, Union

b) Insertion, Deletion

c) extract_min, insertion

d) Union, delete

**Answer: **Insertion, Union

**12. The main distinguishable characterstic of a binomial heap from a binary heap is that**

a) it allows union operations very efficiently

b) it does not allow union operations that could easily be implemented in binary heap

c) the heap structure is not similar to complete binary tree

d) the location of child node is not fixed i.e child nodes could be at level (h-2) or (h-3), where h is height of heap and h>4

**Answer: **it allows union operations very efficiently

**13. The number of trees in a binomial heap with n nodes is**

a) logn

b) n

c) nlogn

d) n/2

**Answer: **logn

**14. In a binomial heap the root value is greater than left child and less than right child.**

a) True

b) False

**Answer: **False

**50+ Binary Heap MCQs with FREE PDF**

**15. What is the basic operation performed in a pairing heap?**

a) merge

b) deletion

c) insertion

d) swapping

**Answer: **merge

**16. If there are c children of the root, how many calls to the merge procedure is required to reassemble the heap?**

a) c

b) c+1

c) c-1

d) 1

**Answer: **c-1

**17. Which of the following methods is the best choice for complex applications?**

a) binary heap

b) d-heap

c) treap

d) pairing heap

**Answer: **pairing heap

**18. Pairing heaps time complexity was inspired by that of?**

a) splay tree

b) treap

c) red-black tree

d) avl tree

**Answer: **splay tree

**19. The roots of the elements of the subtrees are smaller than the root of the heap.**

a) True

b) False

**Answer: **False

**20. The amortized time efficiency for performing deletion of a minimum element is?**

a) O(N)

b) O(log N)

c) O(N2)

d) O(M log N)

**Answer: **O(log N)

**21. Out of the following given options, which is the fastest algorithm?**

a) fibonacci heap

b) pairing heap

c) d-ary heap

d) binary heap

**Answer: **fibonacci heap

**22. What is the run time efficiency of an insertion algorithm?**

a) O(N)

b) O(log N)

c) O(N2)

d) O(M log N)

**Answer: **O(N)

**50+ Pairing Heap MCQs with FREE PDF**

**23. The procedure FindMin() to find the minimum element and the procedure DeleteMin() to delete the minimum element in min heap take _________**

a) logarithmic and linear time constant respectively

b) constant and linear time respectively

c) constant and quadratic time respectively

d) constant and logarithmic time respectively

**Answer: **constant and logarithmic time respectively

**24. Which one of the following array elements represents a binary min heap?**

a) 12 10 8 25 14 17

b) 8 10 12 25 14 17

c) 25 17 14 12 10 8

d) 14 17 25 10 12 8

**Answer: **8 10 12 25 14 17

**25. In a binary min heap containing n elements, the largest element can be found in __________ time.**

a) O(n)

b) O(nlogn)

c) O(logn)

d) O(1)

**Answer: **O(n)

**26. Min heap is a complete binary tree.**

a) True

b) False

**Answer: **True

**27. What will be the position of 5, when a max heap is constructed on the input elements 5, 70, 45, 7, 12, 15, 13, 65, 30, 25?**

a) 5 will be at root

b) 5 will be at last level

c) 5 will be at second level

d) 5 can be anywhere in heap

**Answer: **5 will be at last level

**28. Descending priority queue can be implemented using ______**

a) max heap

b) min heap

c) min-max heap

d) trie

**Answer: **max heap

**50+ Min/Max Heap MCQs with FREE PDF**

**29. Which of the following operations does not destroy the leftist heap property?**

a) insert

b) merge

c) delete

d) swap

**Answer: **delete

**30. What is the fundamental operation on leftist heap?**

a) insertion

b) merging

c) deletion

d) swapping

**Answer: **merging

**31. What is the efficiency of merge used in leftist heaps?**

a) O(N)

b) O(N log N)

c) O(M log N)

d) O(log N)

**Answer: **O(log N)

**32. What is the node path length of a node with 0 or 1 child?**

a) 1

b) -1

c) 0

d) null

**Answer: **0

**33. Why is this heap named leftist heap?**

a) only left subtrees exist

b) the tree is biased to get deep down the left

c) it is balanced

d) right trees are unbalanced

**Answer: **the tree is biased to get deep down the left

**34. In a leftist heap, all the operations should be performed on?**

a) left path

b) centre path

c) right path

d) root

**Answer: **right path

**35. What would be the result if the left subtree of the root has a null path length of 1 and the right subtree has a null path length of 2?**

a) merge occurs without violation

b) violation at left subtree

c) violation at right subtree

d) violation at the root

**Answer: **violation at the root

**36. What happens if the null path length is not updated?**

a) error occurs

b) all null path lengths will be 0

c) all null path lengths will be -1

d) all null path lengths will be 1

**Answer: **all null path lengths will be 0

**50+ Leftlist Heap MCQs with FREE PDF**

**37. What is the fundamental operation performed in skew heaps?**

a) intersection

b) difference

c) merging

d) sorting

**Answer: **merging

**38. What is the time per operation of merging, insertion and deletion operations in a skew heap?**

a) O(N)

b) O(log N)

c) O(N log N)

d) O(N2)

**Answer: **O(log N)

**39. Why would a recursive implementation fail in skew heaps?**

a) skew heaps are self adjusting

b) efficiency gets reduced

c) lack of stack space

d) time complexity

**Answer: **lack of stack space

**40. Which of the following is difficult to determine the right path length?**

a) Skew heaps

b) Binomial tree

c) Leftist heap

d) d-heap

**Answer: **Skew heaps

**41. The worst case analysis for a naïve merge is given as?**

a) O(N)

b) O( log N)

c) O( N log N)

d) O(N2)

**Answer: **O(N)

**42. How many types of the merge are available in skew heaps?**

a) 1

b) 2

c) 3

d) 4

**Answer: **2

**43. Naïve merge cannot be done in a skew merge.**

a) true

b) false

**Answer: **false

**44. What is the amortized efficiency of skew merge?**

a) O(N)

b) O( log N)

c) O( N log N)

d) O(N2)

**Answer: **O( log N)

**45. The worst case running time of all operations in a skew heap is given as?**

a) O(N)

b) O(N log N)

c) O(N2)

d) O(M log N)

**Answer: **O(N)

**50+ Skew Heap MCQs with FREE PDF**

**46. What is the process of building a ternary heap called?**

a) Heapify

b) Hashing

c) Linking

d) Merging

**Answer: **Heapify

**47. Which type of data structure is a ternary heap?**

a) Array

b) Hash

c) Priority Queue

d) Priority Stack

**Answer: **Priority Queue

**48. What is a ternary heap?**

a) An array with three elements

b) Linked list with three elements

c) Tree with three children

d) Heap with all nodes having three children

**Answer: **Heap with all nodes having three children

**49. Who invented d-ary heap?**

a) Carl Rick

b) Alan Turing

c) Donald Johnson

d) Euclid

**Answer: **Donald Johnson

**50. What is the time complexity for inserting a new item in a ternary heap of n elements?**

a) O (log n/ log 3)

b) O (n!)

c) O (n)

d) O (1)

**Answer: **O (log n/ log 3)

**51. What is the time complexity for decreasing priority of key in a minimum ternary heap of n elements?**

a) O (log n/ log 3)

b) O (n!)

c) O (n)

d) O (1)

**Answer: **O (log n/ log 3)

**52. What is the time complexity for increasing priority of key in a maximum ternary heap of n elements?**

a) O (log n/ log 3)

b) O (n!)

c) O (n)

d) O (1)

**Answer: **O (log n/ log 3)

**53. What is the time complexity for deleting root key in a ternary heap of n elements?**

a) O (log n/ log 3)

b) O (3log n/ log 3)

c) O (n)

d) O (1)

**Answer: **O (3log n/ log 3)

**54. What is the time complexity for increasing priority of key in a minimum ternary heap of n elements?**

a) O (log n/ log 3)

b) O (3log n/ log 3)

c) O (n)

d) O (1)

**Answer: **O (3log n/ log 3)

**50+ Ternary Heap MCQs with FREE PDF**

**55. Which of these operations have same complexities?**

a) Insertion, find_min

b) Find_min, union

c) Union, Insertion

d) Deletion, Find _max

**Answer: **Union, Insertion

**56. The Statement “Fibonacci heap has better amortized running time in compare to a binomial heap”.**

a) True

b) False

**Answer: **True

**57. Given a heap of n nodes. The maximum number of tree for building the heap is.**

a) n

b) n-1

c) n/2

d) logn

**Answer: **n

**58. Choose the option with function having same complexity for a fibonacci heap.**

a) Insertion, Union

b) Insertion, Deletion

c) extract_min, insertion

d) Union, delete

**Answer: **Insertion, Union

**59. The main distinguishable characterstic of a binomial heap from a binary heap is that**

a) it allows union operations very efficiently

b) it does not allow union operations that could easily be implemented in binary heap

c) the heap structure is not similar to complete binary tree

d) the location of child node is not fixed i.e child nodes could be at level (h-2) or (h-3), where h is height of heap and h>4

**Answer: **it allows union operations very efficiently

**60. The number of trees in a binomial heap with n nodes is**

a) logn

b) n

c) nlogn

d) n/2

**Answer: **logn

**61. In a binomial heap the root value is greater than left child and less than right child.**

a) True

b) False

**Answer: **False

**50+ Binomial and Fibonacci Heap MCQs with FREE PDF**

**62. The total comparisons in finding both smallest and largest elements are**

a) 2*n +2

b) n + ((n+1)/2) -2

c) n+logn

d) n2

**Answer: **n + ((n+1)/2) -2

**63. Does there exist a heap with seven distinct elements so that the Inorder traversal gives the element in sorted order.**

a) Yes

b) No

**Answer: **No

**64. The leaf node for a heap of height h will be at which position.**

a) h

b) h-1

c) h or h-1

d) h-2

**Answer: **h or h-1

**65. Choose the correct properties of weak-heap.**

a) Every node has value greater than the value of child node

b) Every right child of node has greater value than parent node

c) Every left child of node has greater value than parent node

d) Every left and right child of node has same value as parent node

**Answer: **Every right child of node has greater value than parent node

**66. Left child of parent node has value lesser than the parent node.**

a) True

b) False

**Answer: **False

**67. What is the other name of weak heap?**

a) Min-heap

b) Max-heap

c) Relaxed -heap

d) Leonardo heap

**Answer: **Relaxed -heap

**50+ Weak Heap MCQs with FREE PDF**

**68. What is the fundamental operation performed in skew heaps?**

a) intersection

b) difference

c) merging

d) sorting

**Answer:** merging

**69. What is the time per operation of merging, insertion and deletion operations in a skew heap?**

a) O(N)

b) O(log N)

c) O(N log N)

d) O(N2)

**Answer:** O(log N)

**70. Why would a recursive implementation fail in skew heaps?**

a) skew heaps are self adjusting

b) efficiency gets reduced

c) lack of stack space

d) time complexity

**Answer:** lack of stack space

**71. Which of the following is difficult to determine the right path length?**

a) Skew heaps

b) Binomial tree

c) Leftist heap

d) d-heap

**Answer:** Skew heaps

**72. The worst case analysis for a naïve merge is given as?**

a) O(N)

b) O( log N)

c) O( N log N)

d) O(N2)

**Answer:** O(N)

**73. How many types of the merge are available in skew heaps?**

a) 1

b) 2

c) 3

d) 4

**Answer:** 2

**74. Naïve merge cannot be done in a skew merge.**

a) true

b) false

**Answer:** false

**75. What is the amortized efficiency of skew merge?**

a) O(N)

b) O( log N)

c) O( N log N)

d) O(N2)

**Answer:** O( log N)

**50+ Skew Heap MCQs with FREE PDF**

**76. What is the run time efficiency of an insertion algorithm in d-heap?**

a) O(N)

b) O(log N)

c) O(logd N)

d) O(Nd)

**Answer:** O(logd N)

**77. How many comparisons will occur while performing a delete-min operation?**

a) d

b) d-1

c) d+1

d) 1

**Answer:** d-1

**78. How many basic operations can be performed in a d-heap?**

a) 1

b) 2

c) 3

d) 4

**Answer:** 2

**79. What is the run time efficiency of delete-min operation?**

a) O(log N)

b) O(logd N)

c) O(d logd N)

d) O(d)

**Answer:** O(d logd N)

**80. Multiplication and division to find children and parents cannot be implemented in a d-heap.**

a) true

b) false

**Answer:** false

**81. How many secondary operations are performed in a d-heap?**

a) 1

b) 2

c) 3

d) 4

**Answer:** 4

**82. On which data structure is a d-ary heap based?**

a) stack

b) queue

c) linked list

d) priority queue

**Answer:** priority queue

**50+ D-ary Heap MCQs with FREE PDF**