Question

我是Scala的新手，作为主题

package edu.luc.cs.cs372.echo
package main

object Main extends App {
  val lines = scala.io.Source.stdin.getLines
  val words = lines.flatMap(_.split("\\W+"))
  val list2 = words.groupBy(_.length).mapValues(_.length)
  val vectorOfLengths = (1 to list2.keys.max).map(length =>list2.getOrElse(length, 0))
  for ((count, length) <- vectorOfLengths.zipWithIndex)
    println(f"${length+1}: ${"#" * count}")

此处引发错误：

Error:(7, 21) value groupBy is not a member of Iterator[String]
  val list2 = words.groupBy(_.length).mapValues(_.length)
                    ^

Error:(9, 43) Cannot construct a collection of type That with elements of type (A1, Int) based on a collection of type scala.collection.immutable.IndexedSeq[Nothing].
  for ((count, length) <- vectorOfLengths.zipWithIndex)
                                          ^

如何解决此问题？

Answer 1

words是Iterator，groupBy类上没有Iterator方法，因此您必须将迭代器转换为其他方法：

words.toVector.groupBy(_.length)

如何解决“无法解析groupBy”错误信息？

1 个答案: