View Full Version : K+8P vs K

29-01-2013, 10:26 AM
wKe1,Pa2,b2,c2,d2,e2,f2,g2,h2 (8/8/8/8/8/8/PPPPPPPP/4K3 w).

The Black King is invisible to the White player and is not on the first rank initially.

White wins by checkmating Black, Black wins by playing 100 moves or if White makes an illegal move or if White stalemates.

04-02-2013, 03:57 PM
Not as hard as it looks - to start you off, try the following

[i] Kf1, Kg1 (given that Black King not on first rank so no risk of an illegal move)

[ii] Move right-hand pawn up one, then move the King to the square which the pawn just vacated

[iii] Move each of the remaining pawns up one in order right-to-left

[iv] Apply steps [ii] to [iii] 4 times, until the pawns form a line on the sixth rank and the King is on h5

New problem: White to play and mate in 8 or less.

09-02-2013, 09:14 AM
Solution: The Black King now must be on one of the squares a8-h8

1. Kg5
2. Kf5
3. Pg7 (eliminates squares f8 and h8, but now allows h7)
4. Pf7 (eliminates e8 and g8, but frees h6 in addition to h7)
5. Pg8Q (and checkmate if the Black King was on a8-d8, but adding h5 otherwise)
6. Qg5+ (checkmates if Black King on h5, otherwise forces Kh6-h7)
7. Kf6 (Black: Kh7-h8)
8. Qg7#