Fill the grid with the digits 1 to 9. The digits represent the height of the skyscraper in each cell. Each row, column, 3x3-box and cells of the same color have exactly one of each digit. The clues along the edges tell you how many skyscrapers you can see from that vantage point. There are no neighbouring cells with a difference of 3.
Fill the grid with the digits 1 to 9. Each row, column, 3x3-box and coloured region has exactly one of each digit. There are no neighbouring cells with a difference of 3.
Fill the grid with the digits 1 to 8. Each row, column, 3x3-box and coloured region has exactly one of each digit. One cell is empty. There are no consecutive neighbouring cells.
Fill in the grid so that every row, every column, and every 3x3 box contains the digits 1 through 9. The colored extra-regions must contain each the digits 1 through 9.