A square with a side length of 36 cm can be exactly surrounded by a piece of iron wire. How long is this wire in centimeters?
用一根铁丝正好能围成一个边长36厘米的正方形．这根铁丝长多少厘米．
<gadget id="calculator">36 * 4</gadget>
<output>144</output>

<result>144</result>