Logic Masters Deutschland e.V.

Today is my birthday but I won't say how old I am; it's a secret. Or should I say, it's the secret! Add all the digits in Row 1 of the finished grid and you will get my age! ;o)

It took me quite a few attempts to get a working puzzle with this ruleset, but I'm very happy with the result. Hope you will enjoy it too. Let me know in the comments.



SudokuPad link

Rules

Normal sudoku rules apply:

• Place the digits 1-9 once each in every row, column, and 3x3 box.

• Using all 81 squares in the grid, draw nine one-cell wide snakes. All snakes are unique in length.
• Snakes do not overlap and cannot branch.
• All snakes are C-shaped (i.e. have two 90 degree turns that are in the same direction), but cannot touch themselves (no 2x2 square contains all of the same snake).

• Each snake acts as a between line, where digits along the snake are between the digits at each end, inclusive. (eg. If 3 and 6 are at the ends of the snake, the digits that are allowed on that snake are 3, 4, 5 and 6).

• Each snake contains a cage, which lies entirely within the snake. The digits in a cage add up to the length of the snake it lies within.