A piece of colored paper is 108cm long and 72cm wide. If you want to cut it into small squares of the same size without any residue, what is the maximum side length of the small square in centimeters?
一张彩纸长108cm，宽72cm，要把它截成大小相同的小正方形，而没有剩余，小正方形的边长最大是多少厘米？
<gadget id="calculator">2 * 2 * 3 * 3</gadget>
<output>36</output>

<result>36</result>