Logic Masters Deutschland e.V.

Draw a network of lines through the centers of some cells in the 12x12 grid below. The lines must not leave the 12x12 grid. Cells which do not contain lines contain digits from 1-9.

The Network: The network of lines you draw may freely branch, but the line network must be connected. Additionally, the network has the following properties:

-) Every 2x2 square in the grid contains at least one cell of the line network.

-) If a cell in the network does not orthogonally border a digit, that cell must be a four way intersection.

-) The network contains no loops of any size.

-) Clues on the left and top grid indicate how many cells in that row or column have that many line segments entering/exiting them. For example, the 2 clue indicates how many of the cells have exactly two lines emanating from them.

-) Cells with only one entrance/exit are called dead ends. Each dead end within the network has the property that the sum of all digits in the grid which are orthogonally adjacent to it is 10. Digits may not repeat within one of these sums.

Unvisited cells: Each cell not containing a line contains a digit from 1-9. These digits do not repeat within rows and columns. Additionally, cells containing digits act like the walls in a cave puzzle. That is to say, they are orthogonally connected to the edges of the grid by other cells containing digits.

J-Sums clues: Clues to the right and bottom are standard cryptic Japanese sums clues with values 0-9. Same letters stand for same digits, different letters for different digits. As standard, ? stands for any digit 0-9, and no clue may have a leading zero. (Point of clarification: Digits placed in the grid are 1-9). The ...'s within clues indicate any number of omitted clues including zero.

Below is an example puzzle which uses the digits 1-6 within the grid and the digits 0-6 for the cipher. This puzzle is solvable, and probably 3-4 stars. You can solve the example in penpa here. Links to the full puzzle can be found at the bottom of the page.

Have fun, leave a comment if you enjoy the puzzle!

Play this puzzle in Penpa

Play this puzzle in SudokuPad

PS: I stream solving sudoku like puzzles three days a week. You can check out the channel, as well as some videos I have made about setting puzzles, at my YouTube channel here.