Reworded some of the text for C++ arrays (#24477)

This commit is contained in:
Stephen James
2018-11-19 05:06:07 -06:00
committed by Aditya
parent 61cd176a41
commit 0216725df6

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@ -2,8 +2,8 @@
title: C++ Arrays
---
## What are Arrays?
An array is a series of elements of the same data type which are stored in contiguous memory locations and can be referenced individually.
## What is an Array?
An array is a series of elements of the same data type which are stored in contiguous memory locations and can be referenced as a whole or individually.
Declaration:
dataType arrayName[arraySize];
@ -21,6 +21,7 @@ int numbers [5] = {1, 2, 3, 4, 5};
//Initialization with no values:
int numbers [5] = {};
//In this case the elements in the array are of indeterminate value
//Initialization with fewer values than elements:
int numbers [5] = {6};
@ -30,23 +31,23 @@ int numbers [5] = {6};
//Initialization with declaration:
int numbers [] = {1, 2, 3, 4, 5};
//Note that here the number of values defines the size of the array.
//In the examples above, the size was fixed beforehand
//In the examples above, the size was fixed at compile time
```
## Types Of Arrays
There are two types of arrays based on the way we declare it.
There are two types of arrays based on way the array is declared.
**1**. Static array:
Those arrays whose size is defined before compile time like in the examples above, are called static arrays. In these arrays we can't change their size once they are declared.
**2**. Dynamic array:
Dynamic arrays are those arrays, whose size is not known at compile time and we can define their size at run time. These arrays are created by using **new** keyword and when done with that array we can delete that array by using the **delete** keyword.
Dynamic arrays are those arrays, whose size is not known at compile time and we can define their size at run time. These arrays are created by using **new** keyword and when done with that array we can delete that array by using the **delete** keyword. Specifically, the use of the `delete[]` syntax.
### Access:
Elements from an array can be accessed via reference of their position in the array. (Start counting from 0).
Example:
Elements of an array are accessed using their index. The index of the first element in the array is zero and the second element's index is 1 and so on. You can think of the index of an element as the unit "distance" from the beginning of the array, that is the first element is 0 units from the start.
Examples using the number array from above:
```C++
x = numbers[0]; // = 1. [0] == first position
numbers[2] = 55; // Sets the third position (3) to the new number 55
int x = numbers[0]; // x is assigned 1. index 0 is the first position
numbers[2] = 55; // Sets the third position (index 2) to the new value 55
//numbers[] is now: {1, 2, 55, 4, 5}
```