A snail climbs up a 10-meter-high pillar. It climbs up 5 meters from morning to evening and slides down 4 meters at night. Like this, starting from a certain morning, how many days does it take to climb to the top of the pillar?
一只蜗牛沿着10米高的柱子往上爬，每天清晨到傍晚共向上爬5米，夜间下滑4米，像这样，从某天清晨开始，它需要几天才能爬上柱子的顶端？
<gadget id="calculator">10 - 5</gadget>
<output>5</output>

<gadget id="calculator">5 - 4</gadget>
<output>1</output>

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

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

<result>6</result>