AllYourBase.scala

object AllYourBase extends App {

  def minSec(s: String): Long = {
    val BASE = s.toSet.size max 2
    val dict = collection.mutable.Map.empty[Char, Int]
    (0L /: s) {
      case (acc, char) =>
        acc * BASE + dict.getOrElseUpdate(char, if (dict.size < 2) dict.size ^ 1 else dict.size)
    }
  }

  def process(lineIn: Iterator[String])(lineOut: String => Unit) =
    for (i <- 1 to lineIn.next().toInt) {
      lineOut(s"Case #$i: ${minSec(lineIn.next())}")
    }

  val filename = "A-large-practice"
  val writer = new java.io.PrintWriter(filename + ".out")
  try {
    process(io.Source.fromFile(filename + ".in").getLines) { s =>
      writer.println(s); writer.flush()
    }
  } finally {
    writer.flush(); writer.close()
  }

}

AllYourBaseTest.scala

import org.scalatest._

import AllYourBase._

class AllYourBaseTest extends FunSuite {
  
  test("sample #1") {
    assert(minSec("11001001") === 201)
  }

  test("sample #2") {
    assert(minSec("cats") === 75)
  }
  
  test("sample #3") {
    assert(minSec("zig") === 11)
  }
  
  
  test("sample case") {
    val input = """3
11001001
cats
zig""".lines

    val expected = """Case #1: 201
Case #2: 75
Case #3: 11""".lines

    lineComparison(input, expected)
  }

  test("full small case") {
    val input = io.Source.fromFile("A-small-practice.in").getLines()
    val expected = io.Source.fromFile("A-small-practice.out.ref").getLines()

    lineComparison(input, expected)
  }

  test("full large case") {
    val input = io.Source.fromFile("A-large-practice.in").getLines()
    val expected = io.Source.fromFile("A-large-practice.out.ref").getLines()

    lineComparison(input, expected)
  }

  def lineComparison(input: Iterator[String], expected: Iterator[String]) {
    process(input) { s =>
      for (line <- s.lines) assert(line.trim === expected.next().trim)
    }
    assert(expected.hasNext === false, "Finished too fast.")
  }

}