Scala Bitsets are sets of non-negative integers which are represented as variable-size arrays of bits packed into 64-bit words. The ++:[B>:Int](that: GenTraversableOnce[B]) method is utilised create a collection containing the elements from the left hand operand followed by the elements from the right hand operand.
Method Definition: def ++:[B>:Int](that: GenTraversableOnce[B])
Return Type: It returns a new collection of type That which contains all elements of this collection.
LinkedList(0, 1, 2, 3, 100)
LinkedList(0, 1, 2, 3, A, B)