Skysandoku 3
Rules:
- Classic Sudoku:
Every row, column and 3x3 box must contain every number from 1 to 9.
- Skyscrapers:
Each digit in the grid represents the height of a building in its cell, and taller buildings obstruct the view of shorter ones behind them: clues outside the grid give the number of buildings visible from that vantage point in the clue’s row or column.
- Sandwich Sums:
A circled clue indicates the sum of the digits between 1 and 9 in the indicated row or column. Circled clues are also Skyscraper clues.
Play it online in SudokuPad.
This puzzle is also on Logic Masters Germany.