The puzzles below are current daily and contest puzzles. These puzzles are competitive and you have to register to solve them and participate in the competition. To register click Login link in the top right corner.
You can use the scores page to see the results of other competitors for the daily puzzle.
All the puzzles from the previous days are available at our archive page. Puzzles which are older than 5 days do not affect the score table and can be attempted without registration.
Author: Andrey Bogdanov
Insert a digit from 1 to 5 into every cell, so that each digit appears once in each row and column. Each digit in a cell represents the height of a building. Numbers outside the grid indicate a sum of heights of visible buildings a distant observer could see (at least part of) in that row or column. A building will hide any shorter buildings behind it.
Grid control: Click at a cell reveals the value chooser. Click at the selected value changes the state of the cell. More details about grid control are at the help page.
Author: Anurag Sahay
Shade exactly four connected cells in each outlined region. All shaded cells should form a single connected area without 2×2 groups of cells entirely shaded black. Shaded cells in each outlined region form a tetromino (L, I, T, or S) and two tetrominoes of the same type shouldn't share an edge.
Grid control: Click the mouse button at the selected cell to change the color of the cell. Second click will put auxiliary cross sign, which doesn't affect correctness of the solution, but helps visually. You can also drag the content of one cell to another with the mouse. More details about grid control are at the help page.