```
//配列
var a: [String] = []
var a = ["a", "b", "c", "d"] //推論
```
値にアクセス
```
a[0] //a
a[1...2] //b,c
a[2...] //c,d
a[...2] //a,b,c
a[..<2] //a,b

a[0] = 4; //書き換え
```
追加
```
a.append("f") //最後に
a.insert("f", at: 1) //任意の場所
```
削除
```
a.removeAtIndex(1)
a.removeLast()
a.removeAll() //など
```