public void Admittance(AdmittanceType type)
        {
            switch (type)
            {
            case AdmittanceType.PreOrder: PreOrder(this.root);
                break;

            case AdmittanceType.InOrder: InOrder(this.root);
                break;

            case AdmittanceType.PostOrder: PostOrder(this.root);
                break;
                //default:      |
                //break;    |   --> Not necessary
            }
        }
        public void Admittance(AdmittanceType type)
        {
            switch (type)
            {
            case AdmittanceType.PreOrder: PreOrder(this.root);
                break;

            case AdmittanceType.InOrder: InOrder(this.root);
                break;

            case AdmittanceType.PostOrder: PostOrder(this.root);
                break;

            default:
                break;
            }
        }