How many different divisions are there for distributing the 6 places of "Excellent Young Pioneers" to the first, second and third classes of the sixth grade, each class has at least one place.
将6个"优秀少先队员"的名额分给六年级的一、二、三班，每个班至少1个名额，共有多少种不同的分法．
<gadget id="calculator">6 - 3</gadget>
<output>3</output>

<gadget id="calculator">3 * 1</gadget>
<output>3</output>

<gadget id="calculator">3 * 2</gadget>
<output>6</output>

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

<result>10</result>