Go – Create Array of Specific Length

Arrays in Go are collections of elements with the same type, and their length is fixed and defined at the time of creation. In this tutorial, we will explore the syntax, examples, and best practices for creating and initializing arrays with specific lengths.

Syntax for Creating an Array

The syntax to create an array of a specific length is:

</>
Copy
var arrayName [length]elementType

Here:

  • arrayName: The name of the array.
  • length: The number of elements the array can hold (fixed size).
  • elementType: The type of elements in the array (e.g., int, float64, string, etc.).

Examples of Creating Arrays

Example 1: Create an Array of Integers

Here’s an example of creating an array of integers with a specific length:

</>
Copy
package main

import "fmt"

func main() {
    // Declare an array of 5 integers
    var numbers [5]int

    // Assign values to the array
    numbers[0] = 10
    numbers[1] = 20
    numbers[2] = 30
    numbers[3] = 40
    numbers[4] = 50

    // Print the array
    fmt.Println("Array:", numbers)
}

Explanation

  1. Declare the Array: The array numbers is declared with a fixed length of 5 and element type int.
  2. Assign Values: Individual elements are assigned values using their indices.
  3. Print the Array: The entire array is printed using fmt.Println.

Output

Example 2: Initialize an Array with Values

Arrays can also be initialized with values at the time of declaration:

</>
Copy
package main

import "fmt"

func main() {
    // Declare and initialize an array
    numbers := [5]int{10, 20, 30, 40, 50}

    // Print the array
    fmt.Println("Array:", numbers)
}

Explanation

  1. Declare and Initialize: The array numbers is declared with a fixed length of 5 and initialized with values {10, 20, 30, 40, 50}.
  2. Print the Array: The entire array is printed using fmt.Println.

Output

Example 3: Create an Array of Strings

Here’s an example of creating an array of strings:

</>
Copy
package main

import "fmt"

func main() {
    // Declare and initialize an array of strings
    fruits := [3]string{"Apple", "Banana", "Cherry"}

    // Print the array
    fmt.Println("Array:", fruits)
}

Explanation

  1. Declare and Initialize: The array fruits is declared with a fixed length of 3 and initialized with string values {"Apple", "Banana", "Cherry"}.
  2. Print the Array: The entire array is printed using fmt.Println.

Output

Example 4: Create an Array Using Default Values

If no values are assigned to the array, its elements are initialized with the zero value of the element type:

</>
Copy
package main

import "fmt"

func main() {
    // Declare an array of 4 floats
    var scores [4]float64

    // Print the array
    fmt.Println("Array with default values:", scores)
}

Explanation

  1. Declare the Array: The array scores is declared with a fixed length of 4 and element type float64.
  2. Default Values: Since no values are assigned, all elements are initialized to the zero value for float64, which is 0.0.
  3. Print the Array: The entire array is printed using fmt.Println.

Output

Points to Remember

  • Fixed Length: The size of an array in Go is fixed and cannot be changed after declaration.
  • Zero-Based Indexing: Array elements are accessed using indices starting from 0.
  • Zero Value Initialization: Uninitialized elements in an array default to the zero value of the element type.