scala oneliner
```scala []
object Solution {
  def winningPlayerCount(n: Int, pick: Array[Array[Int]]): Int =
    pick.groupMapReduce(a => (a.head, a.last))(_ => 1)(_ + _).iterator
    .collect{case ((plr,clr),cnt) if plr < cnt => plr}.distinct.length       
}
```
['Hash Table', 'Counting', 'Scala']