In order to attract customers, Xinhuadu Supermarket has prepared some gift boxes "buy two get one free" (buy 2 boxes of toothpaste and get 1 toothbrush free). Now there are 18 boxes of toothpaste and 16 toothbrushes, how many gift boxes can be made at most?
为了吸引顾客，新华都超市准备了一些礼盒"买二送一"(买2盒牙膏送1把牙刷)的活动．现在有18盒牙膏，16把牙刷，最多可以制成多少个礼盒？
<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<result>9</result>