Map diff by 3 text files

import scala.io.Source
import cats.implicits._

object TranslationDiff extends App {
  val ru = Source.fromFile("/home/mitrakov/buffer/ru.txt").getLines().toList
  val en = Source.fromFile("/home/mitrakov/buffer/en.txt").getLines().toList
  val pt = Source.fromFile("/home/mitrakov/buffer/pt.txt").getLines().toList

  val ruMap = ru.map { _.trim.split(":").toList match { case head :: tail => head -> tail.mkString("")}}
  val enMap = en.map { _.trim.split(":").toList match { case head :: tail => head -> tail.mkString("")}}
  val ptMap = pt.map { _.trim.split(":").toList match { case head :: tail => head -> tail.mkString("")}}

  val merged = (ruMap ++ enMap ++ ptMap).groupBy(_._1).mapValues(_.map(_._2).size)
  val sorted = merged.toList.sortBy(_._2)

  sorted foreach println
}