Appeal by defendant from a judgment of the Supreme Court, Kings County, rendered March 1, 1976, convicting him of assault in the first degree, upon a jury verdict, and imposing sentence. Judgment affirmed. The tolling provision for periods of incarceration contained in section 70.06 Penal of the Penal Law constitutes a rational exercise of legislative judgment. A prior felon can properly be required to demonstrate that he can function in society in a law-abiding manner for a 10-year period in order to avoid being sentenced as a recidivist. We find no merit in defendant's other contentions. Cohalan, Acting P.J., Hawkins, Suozzi and Mollen, JJ., concur.