Go Arrays

Arrays are used to store multiple values of the same type in a single variable, instead of declaring separate variables for each value.

Declare an Array

In Go, there are two ways to declare an array:

1. With the var keyword:

Syntax

package main
import ("fmt")

func main() {
  var arr1 = [3]int{1,2,3}
  arr2 := [5]int{4,5,6,7,8}

  fmt.Println(arr1)
  fmt.Println(arr2)
}

[1 2 3]
[4 5 6 7 8]

Example

This example declares two arrays (arr1 and arr2) with inferred lengths:

package main
import ("fmt")

func main() {
  var arr1 = [...]int{1,2,3}
  arr2 := [...]int{4,5,6,7,8}

  fmt.Println(arr1)
  fmt.Println(arr2)
}

Example

This example declares an array of strings:

package main
import ("fmt")

func main() {
  var cars = [4]string{"Volvo", "BMW", "Ford", "Mazda"}
  fmt.Print(cars)
}

Access Elements of an Array

You can access a specific array element by referring to the index number.

In Go, array indexes start at 0. That means that [0] is the first element, [1] is the second element, etc.

Example

This example shows how to access the first and third elements in the prices array:

package main
import ("fmt")

func main() {
  prices := [3]int{10,20,30}

  fmt.Println(prices[0])
  fmt.Println(prices[2])
}

Change Elements of an Array

You can also change the value of a specific array element by referring to the index number.

Example

This example shows how to change the value of the third element in the prices array:

package main
import ("fmt")

func main() {
 prices := [3]int{10,20,30}

 prices[2] = 50
 fmt.Println(prices)
}

Result:

[10 20 50]

Find the Length of an Array

The len() function is used to find the length of an array:

Example

package main
import ("fmt")

func main() {
 arr1 := [4]string{"Volvo", "BMW", "Ford", "Mazda"}
 arr2 := [...]int{1,2,3,4,5,6}

 fmt.Println(len(arr1))
 fmt.Println(len(arr2))
}

Result:

46