13. In a dark storeroom, there are boots of the same size: 12 pairs of black and as many brown. What is the smallest number of boots that need to be taken so that among them there is at least one pair (left and right boot) of the same color, if in the dark it is impossible to distinguish not only the color of the boot but also the left from the right?
13. Let's consider the most "unfavorable" case. If you take 24 shoes, they might all be for one foot. By taking one more shoe, it will definitely match one of the previously taken ones. It is possible that you initially took 12 shoes for different feet but of different colors, but in this case, the result will be the same. Therefore, you need to take 25 shoes.