From the 8 numbers 1--8, at least how many numbers must be taken out to ensure that one of them must be a multiple of the other number.
从1--8这8个数中，至少要取出多少个数，才能保证其中必定有一个数是另一个数的倍数．
<gadget id="calculator">4 + 1</gadget>
<output>5</output>

<result>5</result>