Data Structure Interview Questions & Answers

Data Structure Interview Online Test

Technical interview questions and answers are the foundation of any Data Structure Interview because companies use DSA to test your problem-solving ability, logic building, and coding efficiency. Data Structures such as arrays, linked lists, stacks, queues, trees, and graphs form the backbone of programming, making this topic one of the most important parts of technical rounds. In campus placements and company-specific interviews conducted by TCS, Infosys, Wipro, Cognizant, and Capgemini, these questions decide whether a candidate has strong fundamentals. This guide covers the most important and frequently asked Data Structure interview questions with clear explanations, helping freshers and job seekers understand concepts easily. Preparing these questions improves performance in coding tests, whiteboard interviews, and online assessments.

Computer science professionals should complement their algorithmic knowledge with C language  implementation and Java programming  techniques 

1. Calculate the efficiency of sequential search?

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2. Can we apply binary search algorithm to a sorted linked list, why?

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3. Convert the expression ((A + B) * C - (D - E) ^ (F + G)) to equivalent Prefix and Postfix notations.

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4. Define circular list?

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5. Define double linked list?

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6. Does the minimum spanning tree of a graph give the shortest distance between any 2 specified nodes?

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7. If you are using C language to implement the heterogeneous linked list, what pointer type will you use?

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8. In an AVL tree, at what condition the balancing is to be done?

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9. In RDBMS, what is the efficient data structure used in the internal storage representation?

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10. Is any implicit arguments are passed to a function when it is called?

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11. Is it necessary to sort a file before searching a particular item ?

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12. List out few of the Application of tree data-structure?

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13. List out few of the applications that make use of Multilinked Structures?

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14. List out the areas in which data structures are applied extensively?

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15. Minimum number of queues needed to implement the priority queue?

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16. Parenthesis is never required in Postfix or Prefix expressions, why?

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17. What actions are performed when a function is called?

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18. What actions are performed when a function returns?

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19. What are the advantages of linked list over array (static data structure)?

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20. What are the disadvantages array implementations of linked list?

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21. What are the disadvantages of circular list?

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22. What are the disadvantages of linear list?

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23. What are the disadvantages of representing a stack or queue by a linked list?

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24. What are the disadvantages of sequential storage?

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25. What are the goals of Data Structure?

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26. What are the issues that hamper the efficiency in sorting a file?

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27. What are the major data structures used in the following areas : network data model & Hierarchical data model.

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28. What are the notations used in Evaluation of Arithmetic Expressions using prefix and postfix forms?

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29. What do you mean by free pool?

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30. What do you mean by garbage collection?

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31. What do you mean by overflow and underflow?

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32. What do you mean by recursive definition?

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33. What does abstract Data Type Mean?

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34. What is a linked list?

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35. What is a priority queue?

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36. What is a queue?

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37. What is a spanning Tree?

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38. What is dangling pointer and how to avoid it?

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39. What is data structure?

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40. What is sequential search?

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41. What is the data structures used to perform recursion?

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42. What is the difference between a Stack and an Array?

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43. What is the type of the algorithm used in solving the 8 Queens problem?

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44. Whether Linked List is linear or Non-linear data structure?

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45. If you are using C language to implement the heterogeneous linked list, what pointer type will you use?

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46. Minimum number of queues needed to implement the priority queue?

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47. What is the data structures used to perform recursion?

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48. What are the notations used in Evaluation of Arithmetic Expressions using prefix and postfix forms?

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49. Sorting is not possible by using which of the following methods?

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50. What are the methods available in storing sequential files ?

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51. List out few of the Application of tree data-structure?

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52. List out few of the applications that make use of Multilinked Structures?

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53. In tree construction which is the suitable efficient data structure?

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54. What is the type of the algorithm used in solving the 8 Queens problem?

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55. In an AVL tree, at what condition the balancing is to be done?

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56. What is the bucket size, when the overlapping and collision occur at same time?

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57. Classify the Hashing Functions based on the various methods by which the key value is found.

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58. What are the types of Collision Resolution Techniques and the methods used in each of the type?

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59. In RDBMS, what is the efficient data structure used in the internal storage representation?

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60. What is a spanning Tree?

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61. Does the minimum spanning tree of a graph give the shortest distance between any 2 specified nodes?

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62. Which is the simplest file structure?

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63. Whether Linked List is linear or Non-linear data structure?

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64. What is the difference between a Stack and an Array?

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65. What do you mean by recursive definition?

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66. What is sequential search?

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67. What actions are performed when a function is called?

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68. What actions are performed when a function returns?

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69. What is a linked list?

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70. What are the advantages of linked list over array (static data structure)?

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71. What are the advantages of linked list over array (static data structure)?

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72. Can we apply binary search algorithm to a sorted linked list, why?

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73. What do you mean by free pool?

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74. What do you mean by garbage collection?

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75. What do you mean by overflow and underflow?

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76. What are the disadvantages array implementations of linked list?

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77. What is a queue?

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78. What is a priority queue?

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79. What are the disadvantages of sequential storage?

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80. What are the disadvantages of representing a stack or queue by a linked list?

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81. What is dangling pointer and how to avoid it?

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82. What are the disadvantages of linear list?

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83. Define circular list?

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84. What are the disadvantages of circular list?

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85. Define double linked list?

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86. Is it necessary to sort a file before searching a particular item ?

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87. What are the issues that hamper the efficiency in sorting a file?

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88. Calculate the efficiency of sequential search?

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89. Is any implicit arguments are passed to a function when it is called?

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90. Parenthesis is never required in Postfix or Prefix expressions, why?

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91. What are the major data structures used in the following areas : network data model & Hierarchical data model.

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92. If you are using C language to implement the heterogeneous linked list, what pointer type will you use?

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93. Minimum number of queues needed to implement the priority queue?

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94. What is the data structures used to perform recursion?

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95. What are the notations used in Evaluation of Arithmetic Expressions using prefix and postfix forms?

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96. Convert the expression ((A + B) * C (D E) ^ (F + G)) to equivalent Prefix and Postfix notations.

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97. Sorting is not possible by using which of the following methods?

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98. List out few of the Application of tree data-structure?

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99. List out few of the applications that make use of Multilinked Structures?

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100. in tree construction which is the suitable efficient data structure?

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101. There are 8, 15, 13, 14 nodes were there in 4 different trees. Which of them could have formed a full binary tree?

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102. There are 8, 15, 13, 14 nodes were there in 4 different trees. Which of them could have formed a full binary tree?

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103. In RDBMS, what is the efficient data structure used in the internal storage representation?

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104. One of the following tree structures, which is, efficient considering space and time complexities? a) Incomplete Binary Tree. b) Complete Binary Tree. c) Full Binary Tree.

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105. What is a spanning Tree?

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106. Does the minimum spanning tree of a graph give the shortest distance between any 2 specified nodes?

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107. Whether Linked List is linear or Non-linear data structure?

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108. Can+You+Use+Frequency+Capping+On+The+Search+Network%3f

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