A Level Computer Science OCR Practice Exam

In the context of data structures, what defines a dynamic data structure?

1. It maintains a fixed size during usage

2. It does not allow any user modifications

3. It can change size during run-time

4. It is only applicable for numerical data

The correct answer is: It can change size during run-time

A dynamic data structure is characterized by its ability to grow and shrink in size as needed during program execution, allowing it to effectively manage varying amounts of data. This flexibility is crucial for many applications where the number of elements to be stored is not known in advance or can change over time, such as in linked lists, dynamic arrays, and trees. The option stating that it can change size during run-time is indeed correct, as it highlights the fundamental feature that distinguishes dynamic data structures from static ones, which have a predetermined size that cannot be altered after creation. This adaptability enables dynamic data structures to optimize memory usage and enhance performance for tasks involving elements that have unpredictable growth patterns. In contrast, a fixed size during usage or a lack of user modifications indicates a static data structure, which can be less efficient in scenarios demanding flexibility. The assertion that dynamic data structures are only applicable for numerical data is also incorrect since they can be employed for any data type, including strings, objects, or complex data. This versatility broadens the scope of applications for dynamic data structures in computer science.