There are several small balls of 4 different colors in the bag, at least 2 balls of each color, and 2 balls are randomly drawn each time. To ensure that the result of 8 touches is the same, at least how many times must be touched.
袋中有4种不同颜色的小球若干个，每种颜色的球至少2个，每次任意摸出2个．要保证有8次所摸的结果是一样的，至少要摸多少次．
<gadget id="calculator">7 * 10</gadget>
<output>70</output>

<gadget id="calculator">70 + 1</gadget>
<output>71</output>

<result>71</result>