set的简单的使用方法
//创建一个空setvar letters = Set<Character>()//数组字面量创建set,只能存放stringvar setColors:Set<String> = ["红色","白色","洋红色","黄色"]
//推断存放string类型var setColors:Set = ["红色","白色","白色","洋红色","黄色"]//获取元素数量 ,set 无序的,且无重复的元素 print(setColors,setColors.count)//添加元素setColors.insert("黑色")print(setColors)//查看set是否包含红色if setColors.contains("红色") {print("有你想要的")}else{print("抱歉,还未添加")}//删除元素//删除某个元素setColors.remove("黑色")print(setColors)//删除所有元素 setColors.removeAll()print(setColors)//定义两个setlet numbers1:Set = [1,2,3,4,5]let numbers2:Set = [4,5,6,7,8,]//进行遍历for n in numbers1 {print("无序:\(n)")}for n in numbers1.sorted(){print("有序:\(n)")}//set之间的操作//找出两个set 中相同的元素let newSet = numbers1.intersection(numbers2).sorted()print(newSet)//去除相同元素放到一个新的集合中let newSet1 = numbers1.symmetricDifference(numbers2.sorted())print(newSet1)//合并两个集合let newSet2 = numbers1.union(numbers2.sorted())print(newSet2)//找出numbers1 中 numbers2 不包含的元素let newSet3 = numbers1.subtracting(numbers2.sorted())print(newSet3)//集合之间的关系let a:Set<Int> = [1,2,3,4,5]let b:Set<Int> = [2,3,4]let c:Set<Int> = [4,5,6,7,8]print("b的值是否全部被a包含",b.isSubset(of: a))print("a是否包含b所有的值",a.isSuperset(of: b))print("a是否为b子集集",a.isStrictSubset(of: b))print("a是否为b父集",a.isStrictSuperset(of: b))print("a与c是否没有交集",a.isDisjoint(with: c))
