# Arrays and Slices

> Let's learn about Go's arrays and slices

\ <br>

### Arrays

* In Go, when creating an array, you must specify the **length** of that array
  * ex)

    ```go
    package main

    import "fmt"

    func main() {
     names := [5]string{"chloe", "camila", "bella"}
     names[3] = "charlotte"
     names[4] = "bree"
     fmt.Print(names)
    }
    ```

    * Go's **index** starts from **0**, so in the above example, names\[4] is the 5th index
  * If you put an index larger than the **specified length** when creating an array, an **error** will occur

\ <br>

### Slices

* Sometimes you want to limit the size of an array, but sometimes you want to add elements **without size limitation**
  * The data type you can use in such cases is **slice**
* Slice in Go is an array but **without length**
  * ex)

    ```go
    package main

    import "fmt"

    func main() {
     states := []string{"Florida", "Kentucky"}
     fmt.Println(states)
    }
    ```

    * The only difference from array is that there's no **length**

<br>

#### append()

* When **adding** **items** to a slice, use the `append()` function
* append() takes two arguments:
  1. **slice**
  2. **value**
* However, `append()` does not modify the **slice**
  * `append()` **returns** a slice with new values added!
    * So you need to update the slice again
    * ex)

      ```go
      package main

      import "fmt"

      func main() {
       states := []string{"Florida", "Kentucky"}
       states = append(states, "California")
       fmt.Println(states)
      }
      ```

<br>

*I think I'll probably use slice most of the time!*


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