Santas tsp.scala

val input = """Tristram to AlphaCentauri = 34
Tristram to Snowdin = 100
Tristram to Tambi = 63
Tristram to Faerun = 108
Tristram to Norrath = 111
Tristram to Straylight = 89
Tristram to Arbre = 132
AlphaCentauri to Snowdin = 4
AlphaCentauri to Tambi = 79
AlphaCentauri to Faerun = 44
AlphaCentauri to Norrath = 147
AlphaCentauri to Straylight = 133
AlphaCentauri to Arbre = 74
Snowdin to Tambi = 105
Snowdin to Faerun = 95
Snowdin to Norrath = 48
Snowdin to Straylight = 88
Snowdin to Arbre = 7
Tambi to Faerun = 68
Tambi to Norrath = 134
Tambi to Straylight = 107
Tambi to Arbre = 40
Faerun to Norrath = 11
Faerun to Straylight = 66
Faerun to Arbre = 144
Norrath to Straylight = 115
Norrath to Arbre = 135
Straylight to Arbre = 127"""

val distances =
  input.split("\n")
    .map(_.split("( to | = )"))
    .flatMap(a =>
      List (
        (a(0) -> a(1)) -> a(2).toInt,
        (a(1) -> a(0)) -> a(2).toInt
      )
    ).toMap

val allPlaces = distances.keys.toList.map(_._1).distinct

def recMin(currentDestination: String, remainingDestinations: List[String], distance: Int = 0): Int = {
  if (remainingDestinations.isEmpty) {
    distance
  } else {
    remainingDestinations.map { nextDestination =>
      recMin(nextDestination, remainingDestinations.filter(_ != nextDestination), distance + distances(currentDestination -> nextDestination))
    }.min
  }
}

def recMax(currentDestination: String, remainingDestinations: List[String], distance: Int = 0): Int = {
  if (remainingDestinations.isEmpty) {
    distance
  } else {
    remainingDestinations.map { nextDestination =>
      recMax(nextDestination, remainingDestinations.filter(_ != nextDestination), distance + distances(currentDestination -> nextDestination))
    }.max
  }
}

val min = allPlaces.map(destination => recMin(destination, allPlaces.filter(_ != destination))).min
val max = allPlaces.map(destination => recMax(destination, allPlaces.filter(_ != destination))).max