The students are doing exercises. Xiaoli is the 12th from the left, the 8th from the right, the 5th from the front, and the 15th from the back. How many students are doing exercises?
同学们做操，小丽站在左起第12个，从右起数第8个，从前面数第5个，从后面起第15个，一共有多少名同学在做操？
<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">12 + 7</gadget>
<output>19</output>

<gadget id="calculator">15 - 1</gadget>
<output>14</output>

<gadget id="calculator">5 + 14</gadget>
<output>19</output>

<gadget id="calculator">19 * 19</gadget>
<output>361</output>

<result>361</result>