Xiao Ming cuts a rectangular piece of paper with a length of 18 cm and a width of 12 cm into several largest squares. What is the side length of the largest square in cm?
小明将长18厘米，宽12厘米的长方形纸片剪成几个最大的正方形，求最大正方形的边长是多少厘米？
<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<result>6</result>