Scala 大資料 常用演算法收集

標籤：bsp   ddl   def   ring   amp   var   class   大資料   範圍   

一：IP轉數字，用於比大小，用在求IP段範圍中

  def ip2Long(ip: String): Long = {    val fragments = ip.split("[.]")    var ipNum = 0L    for (i <- 0 until fragments.length){      ipNum =  fragments(i).toLong | ipNum << 8L    }    ipNum  }

二：二分法 尋找某一IP段所屬範圍

  def binarySearch(lines: Array[(Long, Long, String)], ip: Long) : Int = {    var low = 0    var high = lines.length - 1    while (low <= high) {      val middle = (low + high) / 2      if ((ip >= lines(middle)._1) && (ip <= lines(middle)._2))        return middle      if (ip < lines(middle)._1)        high = middle - 1      else {        low = middle + 1      }    }    -1  }

 

Scala 大資料 常用演算法收集