Logic Masters Deutschland e.V.

Rules
Normal sudoku rules apply.
Each clue outside the grid must obey exactly one of the following rules.
1) X-sums: clues indicate the sum of the first X digits, where X is the first seen digit.
2) Sandwich: clues indicate the sum of the digits between the 1 and the 9 in that row/column.
3) 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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