Logic Masters Deutschland e.V.

Link: F-puzzles link to Snake-in-the-Box

Rules:

• -Classic sudoku rules apply.
• -Each Box contains a 9 cell long 1 cell wide orthogonal "pathpix" (a snake that can touch itself orthogonally), with 1 being the head and 9 being the tail. They contain all the digits 1 to 9 once (obviously in this case since they are restrained in a sudoku box).
• -The large circles in each cell indicate digits that are at their correct place in the snake, with 1 always being in first place so always circled and 9 always being in last place so always circled as well. For instance, a circle in in the cell adjacent to the 1 on the snake would necessarily contain a 2, etc (see example picture). All circles are given!
• -the 2 grey vertical inequality signs between two cells indicate an inequality between the digits in these 2 cells.

example :This is a valid pathix constrained within a box
The 4 and 6 are in 4th and 6th position in the snake, while all uncircled digits are not at their correct position (the 3 is in second position, the 8 in third, etc).

Many thanks to Zetamath and his beautiful puzzles for the idea of the circles!