Swfit 常量和变量

import Cocoa//声明一个常量let amp = "marshall"let a = 10//声明一个变量var username = "jackson"var b = 10//声明多个常量let guitar = "jackson", effector = "tc", number = 4//声明多个变量var aa = 1 , bb = 2 , cc = 3//类型标注var name: String = "fender"//改变变量值name = "blackstar"println(name)//变量的值不可以改变let age: Int = 32