There are several chickens and rabbits in a cage. Counting from the top, there are 8 heads, and counting from the bottom, there are 26 feet. How many chickens are there?
笼子里有若干只鸡和兔．从上面数，有8个头，从下面数，有26只脚．有鸡多少只．
<gadget id="calculator">2 * 8</gadget>
<output>16</output>

<gadget id="calculator">26 - 16</gadget>
<output>10</output>

<gadget id="calculator">4 - 2</gadget>
<output>2</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">8 - 5</gadget>
<output>3</output>

<result>3</result>