The Power of Pawns
It's White turn to move, find the minimum number of moves for White to move to win the game.
Note that both players played optimally and that White moves up (pawn).
Assume for the sake of this puzzle that there are more white pieces than originally intended.
Designed by Elangraka Elang.
The answer is 12.
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1 solution
Moderator note:
Nice way to restricting the Black's move! Unusual problem but great nonetheless. Can you post more chess related problems?
Sorry, but your answer seems to be incorrect: 1. Kf5 Kc6, (White's move to block Black's movement). 2. Ke6 Kb6 (Black's only move) 3 a5+ Kc6 (Check) 4 b5 # (Checkmate)
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- a5+ Ka6. Kc6 is not a forced move. This ends in a draw (stalemate or king runs away)
yeah I also realised that.
- pD4 pD5, the black King can't move anywhere else, which causes a checkmate
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That's not a checkmate, it's a stalemate. Game ends in draw.
The black king is already been mated
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No, the White Pawn moves up, they can't move down.
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thank you for solving my my confusion
Vraj is right, because Terza had not mentioned that White is moving up.
Actually, the answer should be 1. The white pawn next to the white king should move up one. The black king would then be unable to move anywhere, except for the white pawns above him.
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According to chess rules if King is unable to move, and he is not in check, games end with draw.
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Correct, that is called stalemate, good job mate XD.
4 moves White King Blocks, black must move 1 to the left, rightmost pawn up 1, King to the left, 2nd rightmost pawn on bottom up 1, King left, left most pawn up 1 check mate
Note it does not say black plays optimally and even so with playing optimally this should work
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I misread the problem, it does say the play optimally but it should still work
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Nope, 1. Kf5 Kc6 2. d5+ Kb6 3. c5+ Ka6 4. a5 Kb5 and the black king slips out.
Thought I'd seen a similar 4-move solution with 4. b5 instead, but again, 4. ... Ka5 and the black king slips out again.
Similarly, the 3-move "solution" 1. Kf5 Kc6 2. d5+ Kb6 3. a5+ gets followed by 3. ... Ka6 which, well... 4. b5+ Kxa5 and the king slips out again, or 4. ??? and stalemate. (Literally any other move - d6, c5, or a king move by White - at that point is a stalemate.)
we can use the white on fifth line,third from left to move forward one step.so it will check,and if the black move away diagonally ,it will checkmate
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Your proposition is usually denoted as 1. d5. However, this is not mate: There is no check!
I can make this check in far less than 12 moves. I'm pretty sure someone else mentioned it as well. 4 moves checkmate
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All 4 move mates here are errors and have been corrected.
King can't anywhere else so it's already checkmate, therefore your answer is incorrect.
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Checkmate means king can't go anywhere AND is in check during his turn: This is not the case here.
4 movies! 1- Kf5 Kc6 2- a5 Kd6 3- Kf6 Kc6 4- b5 #
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Hi Filip, the Black King is already on d6 so after 1. Kf5 the move ...Kc6 is forced. 2 a5 only move Kd6 3. Kf6 only move Kc6 after which b5 indeed is mate. This was my solution as well and I was stumped to find it was wrong! I still believe it is right and this is the fastest way to reach mate: FOUR MOVES.
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@Martin Cohen – No, at this point the king can still come back to d6! It's not a mate
sorry, it can be done in only 5 moves. Taking standard notation, white king starts on square e4 1. Kf5, Kc6 (black's only possible move) 2. Ke5, Kb6 (again, black's only move) 3. Kd5, Ka6 (as before, only possible move for black) 4. pb5+,Kb5 5. pc5# checkmate
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Great problem! Since the starting position has more than the allowed number of pawns, it can't be set up for solution in most chess programs (Stockfish, Hiarcs, Mastersoft Chess, etc.). The sac, followed by the king's tour to protect white's pawns, is delightful. An admission: Trying to solve it without moving pieces, I realized that a sacrifice must be involved, but kept messing up the details of getting the king over to a4, and thought it was unsolveable.
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4 moves 1- Kf5 Kc6 2- a5 Kd6 3- Kf6 Kc6 4- b5 # What is wrong with you guys??!
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It's mate in 2. Push a pawn to cause check, black king moves in front of pawn. Push a second pawn for checkmate.
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Actually, if you push a pawn to cause check ( 1. c5+), the king moves towards your king ( 1. ... K e 6): You can't mate him anymore.
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No you could just move second pawn to checkmate
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@Poonam Singh – That's not checkmate. The black king can move one to the right (Kf6).
It's definitely a 4-move mate and the problem is incorrect - or rather the 12 move solution. 1. Kf5 Kc6 (forced) 2. a5 Kd6 (forced) 3. Kf6 Kc6 (forced) 4. b5 MATE
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pawn -> B4 to B5 : which forces black king to E6. Then White king to E5 and check mate... I don´t see why not?
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Because if the Black King is on e6, Ke5 is illegal.
4 moves ...12 moves is ridiculous.
4 moves: 1) Move white king up 1 diagonal to the right this forces Black king one left as only move, 2) move White king one left again forcing black king to the left. 3) (two options here) advance 3rd pawn from left to place king in check allowing king only two moves right or left. 4) which ever way king moves advance the pawn that puts it in checkmate.
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I don't think that works, because if the king goes to the left, when the passenger puts it in check, he can safely move to at... And then get behind the row of pawns.
On the picture, all of the pieces were white except the black king, so it looked like an illegal position.
The extra Rooks and pawns mean the pawns on the 4th rank can never promote. They can't move backwards, either, so the Black King can't be allowed off the 6th rank. First we have to keep him in front of the a-to-d pawns. Second, we can't let him onto the 5th rank or he'll punch through to the 4th and freedom. I thought I saw a shorter mate, with the White King will wasting a move so every move is a check from then on. That doesn't quite work.
- Kf5 locks the Black King in front of the Pawns. ...... Kc6 -- only legal move.
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a5 Kd6 -- only legal move.
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b5?? doesn't check and takes the only legal move away so that's stalemate, tossing the win.
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c5+?? Kd5! and Black gets behind the Pawns where he can never be checked. No check, no mate, DRAW.
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Kf6! The wasted move! Black still has a move left, and White gets a few checks.
- ...... Kc6 -- only legal move
- b5+ Kd6
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c5+?? Here's the problem. 5 ..... Kd5! The Black King is free.
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Ka3 in the given solution is the same kind of waiting or wasted move as my 3. Kf6 (this note). But I can't cover the holes in the 5th rank when the pawns advance unless I'm right in FRONT of Black. That's why the solution works and the attack from the side doesn't. Interesting!
Actually it can be done in 3 moves King to f5 Pawn to d5 Pawn to a5
Can somebody explain why this does not work? 1. Kf5 Kc6 (only move) 2. a5 Kd6 (only move) 3. Kf6 Kc6 (only move) 4. b5+ Kd6 (only move) 6. c5#
?? advance 1 white pawn= checkmate
Am I missing something here because black is already in checkmate. Why 12 extra moves?
How about 4 moves to checkmate (not 12): 1.Kf5 Kc6, 2.a5 Kd6,3.Kf6 Kc6, 4.b5= checkmate!
I have a problem with this question, the last one also (basically) wanted a minimum number of moves, but that one specified white, and this one didn't specify anything, should we assume when the number of moves isn't assigned, that it's assigned to both? (the answer is 12 moves, but only 6 for white and 6 for black, how do we know if the answer is expecting 6 or 12?)
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The answer will always be 12 moves for one side, not the total number of moves for both sides.
- Kf5 Kc6 (only move)
- Ke5 Kb6 (only move)
- c5+ Kc6 (...Ka6 also met by 4. b5#)
- b5# Right?
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That's not checkmate. 4... Kd6 is a valid move.
3.c5+ Ka6 4.b5 Ka5
Very nice and tough puzzle
Isn't the black king already in check? All I see is a black king and the rest of the pieces are white!?!?
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The king being in check means that he is 'attacked' by any other opponent's piece. Here, there is no threat (i.e. no check)
The white pawns are moving up the board, not down.
But doesn't pawn to d5 make stalemate?
Kf5 Kc6, (White's move to block Black's movement).
a5 Kd6, (Black's only move).
a6 Kc6, (Sacrifice Pawn).
Ke5 Kb6, (Restrict Black to have only one possible move).
d5 Kxa6, (Restrict Black to alternate between a6 and b6).
Kd4 Kb6,
Kc3 Ka6,
Kb3 Kb6,
Ka3 Ka6, ((Restrict Black to have only one possible move to a6).
Ka4 Kb6, (White's move to block Black's movement).
c5+ Ka6, (Check).
b5+ # (Checkmate).