Sequencearray

Sequencearray is a term used in some contexts to describe a data structure that stores an ordered collection of elements in contiguous memory, combining aspects of both arrays and sequences. It is not a universally standardized term, but it often corresponds to what many languages call a dynamic array or vector.

A sequencearray maintains a memory block for elements, along with metadata such as the current size (the number of stored elements) and capacity (the allocated space). Elements are kept in a specific order, allowing indexed access and efficient sequential iteration. The contiguous layout improves memory locality, which can benefit cache performance during traversal.

In practice, a sequencearray may support dynamic resizing. When new elements are appended beyond current capacity, the structure typically allocates a larger block and copies existing elements, increasing capacity usually by a growth factor (often doubling). This yields amortized constant time for append operations, while reallocations incur linear-time costs.

Common operations include access by index, append, insert at a position, delete, replace, and extracting sub-sequences. Access by index is typically O(1), while insertion or deletion at arbitrary positions is O(n) due to element shifting. Iteration is linear, and memory management strategies influence performance for large-scale workloads.

Use cases emphasize fast indexed access and good spatial locality, such as buffers, stacks implemented on top of arrays, and storage of primitive types. Compared with linked lists, sequencearrays offer better cache performance and simpler iteration but may incur higher costs for mid-sequence insertions. Related concepts include fixed-size arrays and higher-level dynamic containers such as vectors and array lists.