RopeIntranet.scala

import scala.io.Source
import java.io.PrintWriter

object RopeIntranet {

  implicit def strToInt(s: String) = s.toInt
  
  implicit class StringWrapper(line: String) {  
    def toRope: Rope = line.split(" ") match {
      case Array(l, r) => Rope(l, r)
    }
  }
  
  val in = Source.fromFile("A-large-practice.in").getLines
  val out = new PrintWriter("A-large-practice.out")
    
  case class Rope(l: Int, r: Int) {
    def isCross(another: Rope): Boolean = l > another.l ^ r > another.r
  }

  case class TestCase(ropes: List[Rope]) {
    def solve: Int = loop(ropes)

    private def loop(ropes: List[Rope]): Int = ropes match {
      case Nil => 0
      case x :: xs => xs.foldLeft(0)((acc, b) => if (x.isCross(b)) acc + 1 else acc) + loop(xs)
    }
  }

  def main(args: Array[String]) {
    val ls = for {
      i <- 1 to in.next
      val ropes = in.take(in.next).toList map (_.toRope)
      val res = TestCase(ropes).solve
    } yield s"Case #$i: ${res}"

    ls.foreach(out.println)
    out.flush
  }
  
}

RopeIntranetTest.scala

import org.scalatest.FunSuite
import org.junit.runner.RunWith
import org.scalatest.junit.JUnitRunner

import RopeIntranet._

@RunWith(classOf[JUnitRunner])
class RopeIntranetTest extends FunSuite{
	
  test("x"){
    val r1 = Rope(10, 20)
    val r2 = Rope(20, 10)
    
    assert(true === r1.isCross(r2))
    assert(true === r2.isCross(r1))
  }
  
  test("x2"){
    val r1 = Rope(10, 10)
    val r2 = Rope(20, 20)
    
    assert(false === r1.isCross(r2))
    assert(false === r2.isCross(r1))
  }
  
  test("x3"){
    val l = """1 10
5 5
7 7""".lines
	val r = l.map(_.split(" ")).map{ case Array(l, r) => Rope(l, r)}.toList
    
	val tc = TestCase(r)
	assert(2 === tc.solve) 
  }
  
}