Question: How to tie a Double Fisherman's Knot
Option 0: Lay the ends of two lines parallel to each other.    Coil the free end of one rope twice around the second rope and pass it back through the inside of the coils.    Repeat with second rope in opposite direction
Option 1: Lay the ends of three lines parallel to each other.    Coil the free end of one rope twice around the second rope and pass it back through the inside of the coils.    Repeat with second rope in opposite direction and then third in same direction
Answer: 0