for index in 1...5 {
  print(index)
}
//如果不需要獲取循環(huán)中每次的循環(huán)次數(shù) 可以使用如下方式
var sum=0;
for _ in 1...3 {
  sum += 1
}

var collection1:Array = [1,2,3,4]
var collection2:Dictionary = [1:1,2:2,3:4,4:4]
var collection3:Set = [1,2,3,4]
for obj in collection1 {
  print(obj)
}
for (key , value) in collection2 {
  print(key,value)
}
for obj in collection3 {
  print(obj)
}

var i=0
//當(dāng)i不小于10時跳出循環(huán)
while i<10 {
  print("while",i)
  i+=1
}
//先進(jìn)行一次操作 在判斷循環(huán)條件
repeat {
  print("repeat while")
} while i<10

var c:Int
if 1>2 {
  c=1
}else if 1<0 {
  c=2
}else{
  c=3
}

var charac:Character = "b"
//使用switch語句進(jìn)行字符分支判斷
switch charac {
case "a":
  print("chara is a")
case "b":
  print("chara is b")
case "c":
  print("chara is c")
default ://default用于處理其他額外情況
  print("no charac")
}
//同一個case中可以包含多個分支
switch charac {
case "a","b","c" :
  print("chara is word")
case "1","2","3" :
  print("chara is num")
default :
  print("no charac")
}
//在case中也可以使用一個范圍
var num = 3
switch num {
case 1...3 :
  print("1<=num<=3")
case 4 :
  print("chara is num")
default :
  print("no charac")
}
//使用Switch語句進(jìn)行元組的匹配
var tuple = (0,0)
switch tuple {
case (0,1):
  print("Sure")
  //也可以只對元組中的某個元素進(jìn)行匹配
case (_,1):
  print("Sim")
  //也可以對元組中的元素進(jìn)行范圍匹配
case(0...3,0...3):
  print("SIM")
default:
  print("")
}
//進(jìn)行數(shù)據(jù)綁定
switch tuple {
case (let a,1):
  print(a)
case (let b,0):
  print(b)
  //let(a,b) 與 (let a,let b)意義相同
case let(a,b):
  print(a,b)
default:
  print("")
}
//對于進(jìn)行了數(shù)據(jù)綁定的Switch語句 可以使用where關(guān)鍵字來進(jìn)行條件判斷
switch tuple {
case (let a,1):
  print(a)
case (let b,0):
  print(b)
//let(a,b) 與 (let a,let b)意義相同
case let(a,b) where a==b:
  print(a,b)
default:
  print("")
}

var tuple = (0,0)
switch tuple {
case (0,0):
  print("Sure")
  //fallthrough會繼續(xù)執(zhí)行下面的case
  fallthrough
  //也可以只對元組中的某個元素進(jìn)行匹配
case (_,0):
  print("Sim")
  fallthrough
  //也可以對元組中的元素進(jìn)行范圍匹配
case(0...3,0...3):
  print("SIM")
default:
  print("")
}

var tmp = 0;
tip:while tmp<10 {
  print("ccc")
  tmp+=1
  switch tmp {
  case 3:
    break tip
  default:
    break
  }
}

var name = "HS"
func nameChange(name:String) {
  guard name=="HS" else{
    print(name)
    return
  }
  print("name is HS")
}

nameChange(name)

if #available(iOS 9, *){
  print("iOS 9")
}