LITS

LITS is a logic puzzle with simple rules and challenging solutions.

The rules of LITS are simple:
You have to place one tetromino* in each region in such a way that:
- 2 tetrominoes of matching types cannot touch each other horizontally or vertically. Rotations and reflections count as matching.
- The shaded cells should form a single connected area.
- 2x2 shaded areas are not allowed.

* Tetromino is a shape made of 4 connected cells. There are 5 types of tetrominoes, which are usually named L, I, T, S and O, based on their shape. The O tetromino is not used in this puzzle because it is a 2x2 shape, which is not allowed.

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Our puzzle websites and apps publish original, programmatically generated logic puzzles. They contain no user-generated content other than player nicknames displayed on leaderboards. There are no comments, chat rooms, forums, file uploads or user profile pages, and puzzles are solved with clicks and selections rather than free-text input.

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