private FastSparseSet(FastSparseSetFactory <E> factory, int[] data, int[] next)
 {
     this.factory           = factory;
     this.colValuesInternal = factory.GetInternalValuesCollection();
     this.data = data;
     this.next = next;
 }
            internal FastSparseSet(FastSparseSetFactory <E> factory)
            {
                this.factory           = factory;
                this.colValuesInternal = factory.GetInternalValuesCollection();
                int length = factory.GetLastBlock() + 1;

                this.data = new int[length];
                this.next = new int[length];
            }