Snakes are laid out on a plane with the following requirements:
- each snake has 3 parts - head, middle, and tail. 
- each part of a snake must touch a different part of another snake (no head-head, middle-middle, tail-tail)
- each snake can only touch another snake at most once
- each snake is touched by exactly one head, one middle, and one tail
- the snakes can't overlap or cross as they are on a plane
What is the minimum number of snakes you need?