Codility Distinct (https://codility.com/demo/results/demoHBXM7Z-JDA/)

CodilityDistinct.scala

object Solution {
    def solution(A: Array[Int]): Int = {
        val positive = new java.util.BitSet()
        val negative = new java.util.BitSet()
        
        A.foldLeft(0) { (current, i) =>
            val duplicate = if (i < 0) (negative get i * -1)
            else (positive get i)
        
            duplicate match {
                case true =>
                    current
                    
                case false =>
                    if (i >= 0) positive set i
                    else negative set i * -1
                    
                    current + 1
            }
        }
    }
}