Logic Masters Deutschland e.V.

Rules
Normal sudoku rules apply.
Each letter represents a different number.
Clues outside the grid are simultaneously numbered rooms clues, sandwich clues, and skyscrapers clues.
Numbered rooms: clues indicate the digit which has to be placed in the Nth cell in the corresponding direction, where N is the digit placed in the first cell in that direction.
Sandwich: clues indicate the sum of the digits between the 1 and the 9 in that row/column.
Skyscrapers: clues indicate how many digits are "seen" by the clue looking into its row/column. Digits are visible when they are larger than all digits before them.

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