Page 30 - Data Structures Interactive Book

Chapter 3

3.1 Introduction to Arrays

Arrays are one of the most fundamental data structures in C++. They provide a way to

store multiple elements of the same type in a contiguous block of memory. Each element in

an array is identified by an index, which allows constant-time access. Arrays are widely used
because they are simple, efficient, and form the basis for more advanced structures such as

matrices, strings, and hash tables.

3.1.1 Definition and Characteristics

An array is a collection of elements arranged sequentially in memory. All elements
must be of the same data type, and the size of the array must be specified at the time of

declaration. Arrays allow random access, meaning any element can be accessed directly using

its index. However, the size of an array is fixed, which can be a limitation when dealing with

dynamic data.

3.1.2 Declaration and Initialization

Arrays in C++ can be declared by specifying the data type, name, and size. Initialization

can be done at the time of declaration or later in the program.

Example:

This declares an array of five integers and initializes them with values.

3.1.3 Memory Representation

Arrays are stored in contiguous memory locations. The index of an array element

corresponds to its offset from the base address. For example, if the base address of

numbers[0] is 1000, then numbers[1] will be at 1004 (assuming 4 bytes per integer). This

contiguous arrangement enables efficient access but also means that resizing arrays is not
straightforward.

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