Scala 统计文件单词数

函数原型：

def foldLeft[B](z: B)(op: (B, A) => B): B = {
    var result = z
    this.seq foreach (x => result = op(result, x))
    result
  }

实现代码：

val lines = Source.fromFile("E://test.txt").getLines()
    val seqop = (result: mutable.HashMap[String, Int], line: String) => {
    val wordcount = line.replace(",", " ").replace(".", " ").replace("(", " ").replace(")", " ").split(" ").filter(_.trim.length > 0).map(word => (word, 1))
    wordcount.foreach(wc => {
        val addOne = (wc._1, result.getOrElse(wc._1, 0) + wc._2)
        result += addOne
      })
      result
    }
    val combop = (result1: mutable.HashMap[String, Int], result2: mutable.HashMap[String, Int]) => {
      result1 ++= result2
    }
     val test =  lines.foldLeft(new mutable.HashMap[String, Int]())(seqop)


    println(test)

文件内容：

one one two
one two three
four two three

运行结果：

Map(one -> 3, three -> 2, four -> 1, two -> 3)