Solution 6
(Online GIPF Puzzle Contest)


Puzzle 6 has more than one solution. White wins with 6 moves!
White cannot prevent Black from recycling pieces. The idea behind this puzzle was to make Black recycle only 3 pieces (i.e. a row including his GIPF-piece) , to leave White a win with 6 moves (i.e. he'll need 5 moves to make Black use his last piece, plus one move to confront Black with the fact that he can't play).
The solution was 1.f7. But that appeared not to be the only solution: 1.i3-f6 is also a sure win in 6 moves. I know that I went through that possibility (the complete sequence of 6 moves), but I must have been confused about something, because I recall that it counted 7 moves. A matter of stupidity. But, it's worse! Even if I had counted the right number of moves following i3-f6, there even appeared to be a third win: 1.i3-f3. I also went through this when checking the puzzle, and I completely missed this one; I hadn't seen White's second move: 1.i3-e3...


Possibility 1: f7


Black had 2 possibilities to make sure to recycle pieces with only 2 moves: 1.d1-d4 and i3-f6. All other possibilities could be countered or would make him lose his GIPF.
Through playing 1.f7 (see diagram), White reduced Black's options to one: he may not play 1…i3-f6 any more because of White's 2.f8-f4. Black would be able to recycle pieces on the a5-i1 diagonal and on the g1-g6 line, but both possibilities leave White a simple win with 3.f8-f3:xGf3.

So, Black must play 1…d1-d4. White defends the piece on d6 with 2.c1-e3, knowing that Black can't capture on the c1-i3 line without losing his GIPF. Again Black has no option and plays 2…i3-f6. Because of the piece on f7 White can capture with (3) f8-f4;x and put pressure on Black's GIPF at the same time. Black, having recycled only 3 pieces, must defend Gf4 with either 3…g7-e7 or h6-e6. The first possibility solves nothing, because White simply re-established the same attack with 4.g7-d6. So, he chooses 3…h6-e6. White can't attack Gf4 with only one move, so he must look for a way to make Black run out of pieces. No problem because, because Black has only 2 pieces left.




Possibility 2: i3-f6

1. i3-f6 / h5;x
2. i4-f4;x / i2-g4
Black can't make a row without including g4 or h3




Possibility 3: i3-f3

1. i3-f3 / i3-f6
2. i3-e3 / h5;x
3. g1-g5;x / i2-g4
4. f7 / d1-d4
5. f8-f4;x / d1-d5;x
6. f8-f2;xGf3

I don't exclude that there might be even a fourth solution, but I must confess that I'm kind of GIPF-blind for the moment. Please send us your solution if it matches a win for White in 6 moves.

Ad Rovers came up with a 4th solution: h1-f3.
That move makes that Black loses the possibility to play 1...d1-d4. It leaves him no other choice then 1...i3-f6. White plays 2.f7, which leaves him an finish similar to solution 1 (see above).

Note: let us know if you find another win for White with 6 moves!



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