There are 31 soldiers who want to cross the river. There is only one small boat by the river. There can only be 6 people on the boat at a time. How many times must the boat carry at least before all of them can cross the river.
有31名战士要过河，河边只有一条小船，船上每次只能坐6人，船至少要载多少次才能全部过河．
<gadget id="calculator">31 - 6</gadget>
<output>25</output>

<gadget id="calculator">6 - 1</gadget>
<output>5</output>

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

<gadget id="calculator">5 + 1</gadget>
<output>6</output>

<result>6</result>