//1.集合是一組不相同的實例的無序組合正好和數(shù)組相反

//2.跟字典一樣,集合內(nèi)的值是無序的

//3.字典的鍵必須唯一,集合也不允許有重復值

//4.為了確保元素單一,就要符合Hashable協(xié)議，類似就跟字典的鍵一樣(一鍵多值但不可以一值多鍵)？

//5.集合存儲單個元素

//6.創(chuàng)建Set集合實例

vargroceryBag =Set(["Apples","Oranges","Pineapple"])

//groceryBag.insert("Apples")

//groceryBag.insert("Oranges")

//groceryBag.insert("Pineapple")

//7.循環(huán)Set集合里面的元素

forfoodingroceryBag{

print(food)

}

//8.集合提供了另一種更方便的語法創(chuàng)建實例這種方法把實例為Set類型的生命和Array的字面量語法相結(jié)合起來

//var groceryBag: Set = ["Apples", "Oranges", "Pineapple"]

//9.集合里是否包含某個元素

lethasBanans =groceryBag.contains("Bananas")

//10.集合的合并去除重復的,留下剩下的元素

letfriendsGroceryBag =Set(["Bananas","Cereal","Milk","Oranges","Apples"])

letcommonGroceryBag =groceryBag.union(friendsGroceryBag)

print(commonGroceryBag)

//union（——：）是Set類型的一個方法,接受一個SequenceType參數(shù),并返回一個Set實例。包含了兩個集合去除重復后的元素

//11.交集留下兩個集合里都有的元素

letroommatesGroceryBag =Set(["Apples","Bananas","Cereal","Toothpaste"])

letitemsToReturn =commonGroceryBag.intersection(roommatesGroceryBag)

//集合提供了intersection(_:)方法來找出同時存在于兩個容器中的元素,并用新的Set實例返回這些元素

//12.如果你想知道兩個元素是否包含共同元素

letyourSecondBag =Set(["Berries","Yogurt"])

letroommatesSecondBag =Set(["Grapes","Honey"])

letdisjoint =yourSecondBag.isDisjoint(with:roommatesSecondBag)

//yourSecondBag里面的元素沒有出現(xiàn)在roommatesSecondBag返回true否則返回false