There is a group of soldiers lined up in a solid square. There are 60 people in the outer layer. How many soldiers are there in total?
有一队士兵排成实心方阵，外层人数共60人，问共多少士兵．
<gadget id="calculator">60 / 4</gadget>
<output>15</output>

<gadget id="calculator">15 + 1</gadget>
<output>16</output>

<gadget id="calculator">16 * 16</gadget>
<output>256</output>

<result>256</result>