CODEWITHSUNDEEP
scala
Ashwin Kumar Padhy
Ashwin Kumar Padhy

Reputation: 19

Comparing nested list of list with a list

I am trying out to compare list of list values with another list and return if matched.I am looking it in scala however i am new into scala and it difficult to do if any suggestions please pass on

val l1 = List(List(1,12.34,76.456,12,List(1,2,3)),List(2,12.43,76.256,12,List(11,12,13)))

val l2 = List(1,2,3,12)

so here trying to compare l1([1,2,3]) with l2 [1,2,3,12] and l1 [11,12,13] with l2 [1,2,3,12] and return if not matched any elements from l1 to l2.

here we are looking for of l1 any value matched with l2 then 0 else 1

Tricky but is it doable in scala?Any suggestions

Upvotes: 0

Views: 192

Answers (2)

Chaitanya
Chaitanya

Reputation: 3638

From the initial set of requirements that you have provided, the following solution will solve your problem

val l1 = List(List(1,12.34,76.456,12,List(1,2,3)),List(2,12.43,76.256,12,List(11,12,13)))

val l2 = List(11,12,13)


l1.flatten.filter(_.isInstanceOf[List[Int]]).map(x =>
  if(x == l2) 0 else 1)

This gives you a result whether the list l2 matches inner list of l1 or not.

res1: List[Int] = List(1, 0)

Upvotes: 0

Gal Naor
Gal Naor

Reputation: 2397

You need to flatten l1. to make it generic (because as I understand, l1 can be list of list of list..) you can create a generic method which flatten it:

def flatten[T](l: List[T]): List[T] = l match {
  case Nil => Nil
  case (x: List[T]) :: tail => flatten(x) ::: flatten(tail)
  case x :: tail => x :: flatten(tail)
}

Then, you can get the result it by:

(l2.map(flatten(l1).contains)).map(_.compare(false)) // List(1,1,1,1)

Here is the code to run and debug - https://scalafiddle.io/sf/3SStZZX/1

Upvotes: 0

Related Questions