其它Kotlin容器

fun main () {
    //创建可变列表
    val myList: MutableList<Int> = mutableListOf(1,2,3,4,5)
    myList.addAll(listOf(1,2,3,4,5))    //其中listOf创建的是不可变列表
    myList.add(8)
    myList.addFirst(0)    
    myList.addLast(10)    
    myList.shuffle()      //随机排列
    myList.sort()         
    myList.reverse()      //反转


    //创建可变字典
    val myMap: MutableMap<Int, String> = mutableMapOf(Pair(1, "John"))
    myMap.put(2, "Jan")
    myMap[3] = "Tom"
    //创建不可变字典
    val newMap: Map<String, String> = mapOf("Smith" to "Teacher", "Julie" to "Classmate")


    //创建可变集合
    val mySet: MutableSet<String> = mutableSetOf("John", "Jan")
    mySet.add("Smith")
    mySet.addAll(setOf("Tom", "Jerry")) //其中setOf创建的是不可变集合
    mySet.remove("Smith")
    mySet.clear()

    println("Is mySet empty? ${mySet.isEmpty()}")
    println("The size of MySet is ${mySet.size}")
    println("The index of \"Smith\" is ${mySet.indexOf("Smith")} ")
}