#Swift
★ 変数の中身を入れ替える
var a = "a"
var b = "b"
swap(&a, &b)
a
//=> "b"
b
//=> "a"
★ タプルで入れ替える
var a = "a"
var b = "b"
(b, a) = (a, b)
★ 絶対値を返す
var a = -10
var b = abs(a)
//=> b = 10
★ 最大値を返す
var m = max(45, 28, 5, 61, 10, 2, 56, 33, 18, 3)
//=> 61
★ 最小値を返す
var m = min(45, 28, 5, 61, 10, 2, 56, 33, 18, 3)
//=> 2