scala的set集合

import scala.collection.mutable
object Test24_1 {
  def main(args: Array[String]): Unit = {
    //1
    val books=mutable.Set("朝花夕拾","活着")
    //2
    books +="三体"

    println(books)
    //3
    books -= "朝花夕拾"
    //4
    val rs=books.contains("朝花夕拾")
    println(s"朝花夕拾是否存在:${rs}")
    //5
    val wang = mutable.Set("朝花夕拾", "活着")
    val yang = mutable.Set("三体", "活着")
    //6
    val rs2 = wang.union(yang)
    println(s"俩个图书馆的并集${rs2}")
    //7
    val rs1 = wang.intersect(yang)
    println(s"两个图书馆的交集${rs1}")
    //8
    val rs3 = wang.diff(yang)
    println(s"俩个图书馆的差集${rs3}")
  }
}