From a rectangular piece of paper with a length of 8 cm and a width of 5 cm, a square piece of paper as large as possible is cut out, what shape is the remaining part? What is the remaining circumference in centimeters?
从一张长8厘米，宽5厘米的长方形纸片中，剪去一个尽可能大的正方形纸片，剩下的部分是什么图形？剩下的周长是多少厘米？
<gadget id="calculator">8 - 5</gadget>
<output>3</output>

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

<gadget id="calculator">8 * 2</gadget>
<output>16</output>

<result>16</result>