Scala List

scala 可变列表与不可变链表

package com.cslc.day2

object listApp {
  def main(args: Array[String]): Unit = {
    val l=List(1,2,3,4,5)
    println(l.head)
    println(l.tail)
    //list 头部新增
    val l2=1::Nil
    println(l2)
    //可变的列表
    val  cl1=scala.collection.mutable.ListBuffer[Int]()
    cl1+=1
    cl1+=2
    println(cl1)
    cl1++=List(8,9,8,98,9,9)
    println(cl1)
    //插入
    cl1.insert(2,100,101,102)
    println(cl1)
    cl1.append(999,998)
    println(cl1)
    //删除
    cl1.remove(1,2)
    println(cl1)
    cl1.trimEnd(2)
    println(cl1)
    println(SUM(1,2,3,4))
  }
  def SUM(nums:Int*): Int ={
    if (nums.length==0){
      0
    }else{
      nums.head+SUM(nums.tail:_*)
    }
  }
}