There are 6 small wooden blocks of red and green in the cloth bag, each with the same shape and size. If you want to ensure that you can take out 2 wooden blocks of different colors from the cloth bag at a time, how many small wooden blocks must you take out at least?
布袋里有红、绿两种小木块各6块，形状大小都一样，如果要保证一次能从布袋里取出2块颜色不同的木块，至少必须取出几块小木块？
<gadget id="calculator">6 + 1</gadget>
<output>7</output>

<result>7</result>