How many ways are there to exchange a piece of RMB of 1 yuan into several pieces of RMB of 1 jiao, 2 jiao, and 5 jiao?
将一张1元的人民币兑换成若干张1角、2角、5角的人民币，共有多少种兑换方法．
<gadget id="calculator">5 - 2</gadget>
<output>3</output>

<gadget id="calculator">6 + 3 + 1</gadget>
<output>10</output>

<result>10</result>