There are three identical boxes of apples and oranges, except one contains all apples, one contains all oranges, and one contains a mix.
The boxes are labeled “apples”, “oranges”, and “apples and oranges” but all 3 boxes were labeled incorrectly!
You have the opportunity to inspect fruit from the boxes one at a time, without looking inside the box. What is the fewest number of fruit you need to inspect to correctly label the contents of the identical boxes?
This was a popular brainteaser in some engineering interviews a while back, including a software quality assurance engineer interview at Apple.
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