Question: No can opener and a can of beans.
Option 0: Find a rock or cement surface, needs to be rough. Rub the top of the can over and over against this rough surface until the joining seam has been filed completely away and now you can open the can.
Option 1: Find a rock or cement surface, needs to be rough. Rub the top of the can over and over against this rough surface until the rock has been filed completely away and now you can open the can.
Answer: 0