Find elements in a list that are not in the second list (in scala)

Question

Suppose I have two lists:

val a = List(\'a\', \'b\', \'c\')
val b = List(\'a\', \'b\', \'c\', \'d\')

I want to get the element which is not in

Answer 1

You can use diff for this:

scala> b diff a
res1: List[Char] = List(d)

You probably want to work with Set if you are doing diff.