//定义枚举

enum MapDirection {

case North

case South

case East

case West

func simpleDescription() -> String {

switch self {

case .North:

return "North"

case .South:

return "South"

case .East:

return "East"

case .West:

return "West"

}

}

}

// 使用枚举

let en: MapDirection = MapDirection.North

var en = MapDirection.North

print(en.simpleDescription())

en = .West

print(en.simpleDescription())

//定义结构体

struct Summation {

var addend: Int

var augend: Int

var addstring: String

var augstring: String

func sum() -> Int {

return addend + augend

}

func sumstring() -> String {

return addstring + augstring

}

}

//创建一个结构体

//        let newStruct = Summation(addend: 10, augend: 20)

let newStruct = Summation(addend: 10, augend: 20, addstring: "newStruct", augstring: "newStruct")

//使用结构体内的方法

let sum = newStruct.sum()

print(sum)

print(newStruct.sumstring())