golang variable length array

Golang is a fast and efficient programming language. Its native arrays can be of fixed length, but in many scenarios, we need to use arrays with non-fixed lengths. So in this case, how can we use golang to build a variable-length array?

Slice can be used in golang to construct variable-length arrays. It is a reference type and can achieve dynamic growth. A slice is composed of three parts, namely the pointer to the underlying array, the length and capacity of the slice. It is used similarly to an array, but with some extensions.

In golang, use the make() function to create slices. The make() function creates an array and returns a reference to the array. This reference is the slice. The make() function accepts two parameters, the first parameter is the type of the array, and the second parameter is the length of the array. Of course, the length of the slice does not need to be determined at creation time and can be any value.

Use the append() function to add elements to the slice. When elements are added to a slice, the slice will automatically expand if there is insufficient capacity. It should be noted that the capacity of each expansion is twice the previous one.

The following is a simple example showing how to use slicing to construct a variable-length array:

package main

import "fmt"

func main() {
    var arr []int
    arr = make([]int, 0)

    arr = append(arr, 1, 2, 3, 4, 5)

    fmt.Println(arr)
}

In the above example, we first declare a variable arr and initialize it to be empty slice. Then, we use the make() function to create an array of int type with a length of 0 and assign it to arr. Next, we use the append() function to add elements to arr. Finally, we print out the value of arr.

In addition to using the make() function to create slices, there is another way to create slices. When declaring a slice variable, you can directly specify the value of the slice. This method is also called a slice literal:

package main

import "fmt"

func main() {
    arr := []int{1, 2, 3, 4, 5}

    fmt.Println(arr)
}

In the above example, we directly declare a slice variable arr and initialize it as An array of type int containing 5 elements.

To summarize, a slice in golang is a variable-length array that can grow dynamically. Use the make() function to create a slice, and use the append() function to add elements to the slice. A slice is a reference type that can be referenced by multiple variables. Modifying the value of one variable will affect the values ​​of all variables that reference the slice. Therefore, care needs to be taken in how slices are used and passed around.

The above is the detailed content of golang variable length array. For more information, please follow other related articles on the PHP Chinese website!