Tetris Quads
(Published on 18. October 2025, 12:28 by Artham)
Normal Sudoku rules apply.
Divide the grid in blocks of four cells connected orthogonally (Tetris shapes) so that no block overlaps on another block or on a highlighted square. Every possible shape must be represented once, as well as all its symmetric counterparts (by rotation or mirroring).
Circles are placed between cells of which two cannot belong to the same block (all circles are given). Every digit in a circle has to be assigned to a surrounding cell.
Inside a block, digits orthogonally connected must have a difference of at least 3.
Solution code: Last row from left to right
Comments
on 19. October 2025, 00:23 by Artham
You understood it well the fist time. The red cells are what's referred to as "highlighted squares" in the rule. The blocks will eventually cover all white squares and leave the red ones untouched. There is a way to place blocks around r6c2 so that both circles touch 3 blocks, apart from the red square.
on 19. October 2025, 00:14 by butch02
Red cells are the highlighted squares and are not included in Tetris shapes
on 18. October 2025, 22:42 by jem55
What do the red cells mean? I am a bit confused about the wording in the instructions where it says "two cannot belong to the same block (all circles are given)". At first I thought you meant that all cells around a circle must belong to different blocks but looking at r6c2 this cannot be the case... Could you please clarify for me?
