//enum direction {
//    case north
//    case south
//    case west
//    case east
//}  等价于下面写法
enum direction {case north,south,west,east
}var dir = direction.north
dir = .south
dir = direction.west
//print(dir)switch dir  {
case .south :print("south")
case .north :print("north")
case .east :print("east")
case .west :print("west")
}
//输出 west

enum score {case point (Int)case grade (Character)
}
var sc = score.point(10)
sc = .grade("A")//print(sc)switch sc {
case let .point(i):print("分数\(i)")
case let .grade(i):print("等级\(i)")
}
//输出 等级Aenum date{case ymd (Int,Int,Int)case string (String)
}var d = date.ymd(2005, 8, 8)
//d = .string("2008-8-8")switch d {
case let .string(i):print("sting时间\(i)")
case let .ymd(a, b, c): // .ymd(let a,let b,let c):print("时间\(a)-\(b)-\(c)")
}
//时间2005-8-8 输出

enum grade :String{case perfect = "A"case great = "B"case good = "C"case bad = "D"
}
print(grade.perfect.rawValue) //A
print(grade.great.rawValue)//B
print(grade.good.rawValue)//C
print(grade.bad.rawValue)//D

//t如果枚举初始值类型为int \ String  Swift 会为其自动分配原始值
enum time :Int { //默认值 0 1 2case morning , afternoon ,evening
}
print(time.afternoon.rawValue) // 1
enum direction : String { //默认值就是当前字符串case north,south,west,east
}

indirect enum mathExpor{case num(Int)case sum(mathExpor,mathExpor)case difference(mathExpor,mathExpor)
}
let one = mathExpor.num(8)
let two = mathExpor.num(5)
let three = mathExpor.num(3)
let sum = mathExpor.sum(one, two)
let difference = mathExpor.difference(sum, three)func calcute (_ math:mathExpor )->Int{switch math {case let .num(i):return icase let .sum(i, j):return calcute(i)+calcute(j)case let .difference(i, j):return calcute(i)-calcute(j)}}
print(calcute(difference)) //10

enum passWord{case num(Int,Int,Int,Int) // int 8字节 * 4 = 32case  string              // 分配一个字节
}
print(MemoryLayout<passWord>.stride) //40 分配占用空间大小
print(MemoryLayout<passWord>.size) //33 实际占用空间大小
print(MemoryLayout<passWord>.alignment) //8 对齐参数

var pwd  = passWord.string
print(MemoryLayout.size(ofValue: pwd))  // 33
print(MemoryLayout.stride(ofValue: pwd)) //40
print(MemoryLayout.alignment(ofValue: pwd)) //8
pwd = .num(100, 1, 2, 40)
print(MemoryLayout.size(ofValue: pwd))  // 33
print(MemoryLayout.stride(ofValue: pwd)) //40
print(MemoryLayout.alignment(ofValue: pwd)) //8