如何获得哈希图 Scala 值的可能对组合

Question

我有一个 hashmap 如下：

val hm : HashMap[Int, List[String]] =
  HashMap(
    1 -> List("Eat", "Drink","Sleep", "work"),
    2 -> List("Eat", "Sleep","Dance"),
    3 -> List("Write", "Print","Dance")
  )

我想检索此散列映射值的可能对，return 分别在列表中检索每一对我将组合函数用作

hm.mapValues(_.combinations(2).toList)

结果是：

 Map(1-> List(List(Eat, Drink), List(Eat, Sleep), List(Eat, work), List(Drink, Sleep), List(Drink, work), List(Sleep, work)), 2-> List(List(Eat, Sleep), List(Eat, Dance), List(Sleep, Dance)), 3 -> List(List(Write, Print), List(Write, Dance), List(Print, Dance)))

但预期的结果应该是三个列表

List(List("Eat", "Drink","Sleep", "work"),List("Eat", "Sleep","Dance"))
List( List("Eat", "Drink","Sleep", "work"),List("Write", "Print","Dance"))
List(List("Eat", "Sleep","Dance"), List("Write", "Print","Dance"))

我错过了什么

Answer 1

仅使用地图的值：

hm.values.toList.combinations(2).toList

https://scalafiddle.io/sf/ZGbHC4c/0

如何获得哈希图 Scala 值的可能对组合

How to get the possible pair combinaisons of values of a hashmap Scala

combinations

scala

hashmap

pairwise