标题被主播吃掉了

1.1最大数

object basic52 {
  def main(args:Array[String]): Unit = {
    val arr = Array(-1,2,30,5)
    val rst = arr.reduce((x,y)=> if(x>y)x else y)
    println(s"rst=${rst}")
  }
}

1.2

object basic52 {
  def main(args:Array[String]): Unit = {
    val arr = Array(1,2,3,4)
    //val rst = arr.reduce((x,y)=> if(x>y)x else y)//
    val rst = arr.reduceRight((x,y) => x-y)
    println(s"rst=${rst}")
  }
}

1.3

object basic52 { def main(args:Array[String]): Unit = { val arr = Array(1,2,3,4) //val rst = arr.reduce((x,y)=> if(x>y)x else y)// val rst = arr.fold(10((x,y) => x+y)) println(s"rst=${rst}") } }

1.4排序

object basic52 {
  def main(args: Array[String]): Unit = {
    Array(-1, 2, 0, 4, 9).sortWith((x, y) => Math.abs(x - 0) < Math.abs(y - 0)).foreach(println)
  }
}

1.5排序

object basic52 { def main(args: Array[String]): Unit = { // Array(-1, 2, 0, 4, 9).sortWith((x, y) => Math.abs(x - 0) < Math.abs(y - 0)).foreach(println)// Array(-1,2,0,4,9).sortWith((x,y)=> x>y).foreach(println) } }