3 boys and 2 girls stand in a row, the boys must be separated, how many ways are there?
3个男生2个女生站成一排，男生必须隔开，问有几种排法？
<gadget id="calculator">3 * 2 * 2 * 1 * 1</gadget>
<output>12</output>

<result>12</result>