From WPC unofficial wiki


Snake Ends Example.png Snake Ends Example Solution.png

Draw a snake, i.e. a 1 cell-wide single continuous path in the grid whose head and tail are given. The snake does not touch itself, even diagonally. Numbers outside the grid indicate the number of snake cells in that row/column.

(Rules and example from WPC 2017 IB)

Rule Variations[edit]

There are a lot.

  • Endpoints are not given.
  • Length of a snake is given.
  • Snake's midpoint (for example 23rd cell in a 45-cells long snake) is given.
  • Some cells with snake segments are given.
  • A puzzle from WPC 2018/Round 7 had "E/O" clues outside the grid that stand for even and odd.
  • A puzzle from WPC 2016/Round 12 required the snake to go through every given letter in a given order.
  • Snaky Loop: Instead of a snake, locate a loop that doesn't touch itself.

History of the puzzle[edit]

Probably first appeared under the name "Nessie" in WPC 1996. The author is unknown.


See list of Snake variants.

Appearances in the past WPCs[edit]

Listed here are appearances of classic to almost-classic Snakes. For variants, see list of Snake variants#Appearances in the past WPCs.