编辑代码

object Hello extends App {
    var s1 = Set(-10, 5 , 1 , 2 , 3 , 4 ,5)
    var s2 = Set(-2, 4 , 5 , 6 , 7 , 8)
    s1 = s1 + 9
    s2 = s2+ 9 + 10
    s1.drop(2)
    s2.dropRight(3)
    if(s1.contains(4) && s2.contains(4))
    println("Yes")
    else
    println("No")
    println(s1.&(s2)) //s1和s2交集
    println(s1++(s2)) //s1和s2并集
    println(s1.diff(s2)) //s1和s2差集


    println(s1.max)
    println(s2.min)

}