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7&8 of Puzzle_Round1_IB_v2

Hi,
please explain to me about These puzzles :
7&8 of http://gp.worldpuzzle.org/sites/default/files/Puzzle_Round1_IB_v2.pdf

7. Magnets (43 points) [Gabi Penn-Karras
8. No Four in a Row (61 points) [Roland Voigt
I can not solve them. Please tell me that "how to solve".
Thank you/Shaghayegh

Hello Shaghayegh, the solving technique can not be explained now but some players might comment their steps after the tournament. As for the instructions - No Four in a Row puzzle - the example just uses the basic solving technique (whenever there are three X in a row, enter an O in the fourth cell, and vice versa; repeat). For the Magnets however, the example is a bit more difficult, so please explain exactly what is unclear. Thank you

For how to solve magnet in general, I write the excess/deficient of +'s the rows/columns. This tells me how many vertical/horizontal magnets must be used at minimum, as well as the parity. If you do this on the sample puzzle, you will find that you need 1 vertical from row 4 to row 5, and 1 vertical from row 5 to row 6. That forces the horizontal block in row 5 to be a magnet (of +/-, once you do the count for columns). This tells that the horizontal block in row 4 must be shaded, as well as which of the 2 vertical block from rows 4 to row 5 must be shaded. The rest of the puzzle is no more complicated than what I described here, but I will let you work it out yourself.

Of course, I cannot say how much harder the actual puzzle will be, having never seen it.