Zhang Hua has 5 classmates on the left and 7 classmates on the right. How many people are there in this row? How many
张华左边有5个同学，右边有7个同学，这一排共有几个人？多少
<gadget id="calculator">5 + 7 + 1</gadget>
<output>13</output>

<result>13</result>