In the basement of the lab, mandrakes grow endlessly, providing an unlimited supply of mandrake extract. You have two measuring cups: 5 ml and 7 ml.
Warning: At no point can any cup contain exactly 3 ml—otherwise the mandrakes will scream and destroy the laboratory!
Goal: Measure exactly 4 ml of extract.
You can:
But remember: if any cup ever contains exactly 3 ml, you fail!
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