From the birth of the Communist Party of China on July 1, 1921 to the founding of the People's Republic of China on October 1, 1949, how many months have passed.
从1921年7月1日中国共产党诞生，到1949年10月1日中华人民共和国成立，经过了多少个月．
<gadget id="calculator">1_949 - 1_921</gadget>
<output>28</output>

<gadget id="calculator">28 * 12</gadget>
<output>336</output>

<gadget id="calculator">10 - 7</gadget>
<output>3</output>

<gadget id="calculator">336 + 3</gadget>
<output>339</output>

<result>339</result>