majidazimi

import java.util.Arrays
import scala.reflect.ClassTag
import scala.collection.AbstractIterator

/**
 * Conceptually, a map where the (implicit) keys are positive `Int` values and the values are
 * non-`null`; `null` values are not permitted!
 * The key values always have to be larger than or equal to 0 and are ideally continues
 * (0,1,2,3,...). The values are stored in a plain array to enable true O(1) retrieval.
 * Furthermore, the array is only as large as it has to be to keep the value associated