Problem 2: Two witches are mixing a brew in a cauldron when the recipe calls for exactly 4 pints of yak sweat. They have a bucketful of yak sweat but no 4-pint measure. They have a pitcher that hold exactly 5 pints and a pot that holds exactly 3.

Fill the 3-Pint-Pot from bucket, and put its content into the 5-Pint-Pitcher.
Fill the 3-Pint-Pot again from the bucket, and fill up the 5-pint-pitcher. This leaves 1 pint in the pot. Put that into the cauldron.

Fill the 3-Pint-pot from the pitcher. Empty the pitcher into the cauldron.

Now 4 pints went into the cauldron.

The remaining 2 pints in the pitcher may be poured back into the bucket.