In computer science, a data structure is a format in which data is organized and stored, usually chosen to access the data efficiently. More precisely, a data structure is a set of data values, the relationships between them, and the functions or operations that can be applied to the data, i.e. it is an algebraic structure about the data.
Data structure, as the basis of abstract data type (ADT), defines the logical form of data.
Different types of data structures are suitable for different application needs, and some are even designed for specific tasks.
For example, relational databases often use B-tree indexes for data retrieval, while compiler implementations often use hash tables to look up identifiers. Data structures provide an efficient way to manage large amounts of data, especially in the use of large databases and Internet indexing services.
When designing efficient algorithms, efficient data structures are often a key factor. Certain formal design methods and programming languages emphasize data structures, not just algorithms, as key organizing factors in software design. Data structures can be used to organize the storage and retrieval of information, which can be stored in primary and secondary memory.
Data structures can be implemented using a variety of programming languages and techniques, but they all share the common goal of organizing and storing data efficiently. Data structures basically rely on the computer's ability to access and store data by pointers in its memory. A pointer is a string of bytes that represents a memory address and can be stored in the memory itself and manipulated by the program. Thus, array and record data structures are based on calculating the addresses of data items using arithmetic operations, whereas linked list data structures are based on storing the addresses of data items within the structure itself.
This approach to data structuring has a profound impact on the efficiency and scalability of algorithms.
For example, contiguous memory allocation in arrays facilitates fast access and modification operations, leading to performance optimization in sequential data processing situations.
The implementation of a data structure usually requires writing a set of programs to create and manipulate instances of the structure. The fact that the efficiency of a data structure cannot be analyzed separately from these operations emphasizes the theoretical concept of an abstract data type: a data structure that is indirectly defined by the operations it can perform and its mathematical properties.
There are many types of data structures, often built on simpler primitive data types. Common examples include:
It is necessary to choose the corresponding data structure according to specific needs. For example, if frequent random access is required, an array may be an ideal choice; if frequent insertions and deletions are required, a linked list may be more suitable.
Most low-level languages lack built-in support for data structures, but many high-level programming languages provide specific syntax or built-in support. For example, the C and Pascal languages support records and structures, and most programming languages usually have some kind of library mechanism so that different programs can reuse implementations of data structures.
Modern programming languages generally provide standard libraries to implement the most common data structures, such as the C++ Standard Template Library and the Java Collections Framework.
Many known data structures have concurrent versions, allowing multiple computing threads to access an instance of a specific data structure simultaneously.
Choosing an appropriate data structure can show whether the design is good or not, and this reflects the effectiveness of the technology in solving the problem. Have you considered the impact of choosing a different data structure in a specific situation?