How to Create an Array in Go

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In this article, we will cover the basics of creating and using arrays in Go. We will discuss the different types of arrays that can be created in Go, and provide examples of how to declare and initialize arrays.



Declaring an Array

In Go, you can declare an array by specifying its size and the type of elements it will contain. The syntax for declaring an array is as follows:

var arr [size]type

Here, arr is the name of the array, size is the number of elements in the array, and type is the data type of each element. For example:

var numbers [5]int

This declares an array called numbers with 5 integer elements.

Initializing an Array

Once you have declared an array, you can initialize its elements by assigning values to them. You can do this using the following syntax:

arr[i] = value

Here, i is the index of the element you want to assign a value to, and value is the value you want to assign. For example:

numbers[2] = 7

This sets the third element in the numbers array to the value 7.

Accessing Array Elements

Once an array has been initialized, you can access its elements by using their indices. The syntax for accessing an element is as follows:

arr[i]

Here, i is the index of the element you want to access. For example:

fmt.Println(numbers[2]) // prints 7

This prints the value of the third element in the numbers array, which is 7.

Slicing an Array

In Go, you can create a slice of an array by specifying the indices of the elements you want to include in the slice. The syntax for slicing an array is as follows:

arr[i : j]

Here, i and j are the indices of the first and last elements you want to include in the slice, respectively. For example:

numbers := [5]int{1, 2, 3, 4, 5}
slice := numbers[1 : 3] // creates a slice containing elements 2-4
fmt.Println(slice)      // prints [2, 3, 4]

This creates a slice called slice that contains the values of the second, third, and fourth elements in the numbers array, which are 2, 3, and 4, respectively.

Multi-dimensional Arrays

Go also supports multi-dimensional arrays, which are arrays whose elements are themselves arrays. The syntax for declaring a multi-dimensional array is as follows:

var arr [size1][size2]type

Here, arr is the name of the array, [size1] and [size2] are the sizes of each dimension, and type is the data type of each element. For example:

var matrix [3][5]int

This declares a multi-dimensional array called matrix with 3 rows and 5 columns, each containing an integer value.

Conclusion

Arrays are a fundamental part of the Go programming language, and they provide a powerful way to store and manipulate collections of data. By following the examples in this article, you should be able to create and use arrays in your own Go programs.


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