How many zeros are there at the end of the product of the formula 1*2*3*...*124*125?
算式1*2*3*…*124*125的积末尾有多少个零．
<gadget id="calculator">125 / 5</gadget>
<output>25</output>

<gadget id="calculator">125 / 25</gadget>
<output>5</output>

<gadget id="calculator">125 / 125</gadget>
<output>1</output>

<gadget id="calculator">25 + 5 + 1</gadget>
<output>31</output>

<result>31</result>