A frog climbs a well that is 10 meters high. It climbs 3 meters at a time during the day, but slides down 2 meters at night. How many times does it have to climb to reach the mouth of the well?
青蛙爬一口10米高的井，白天每一次爬3米，但晚上又向下滑2米，它要爬多少次才能爬上井口？
<gadget id="calculator">10 - 3</gadget>
<output>7</output>

<gadget id="calculator">3 - 2</gadget>
<output>1</output>

<gadget id="calculator">7 / 1</gadget>
<output>7</output>

<gadget id="calculator">7 + 1</gadget>
<output>8</output>

<result>8</result>