There is a snail in a dry well of 10 meters. It climbs up 3 meters during the day and slides down 2 meters at night. How many days will it take for the snail to climb out of the dry well?
一个10米的枯井里有一张蜗牛，它白天向上爬3米，夜里往下滑2米，多少天后蜗牛爬出枯井？
<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>