Pawn battle

[admin]

The goal of this puzzle is to determine if from a position in a pawn battle game you can make a move that garantees a win in the future if you always play perfectly.

Go to puzzle

[demo]

a few questions.
1. "we will assume that all positions are given are happening some time after each player made its first move." I don't understand it, I think there's solecism.
2. what does "G2" mean in the output?
3. Does white always plays first?

[admin]

1. It should be only "are happening". What we mean here is you can move by any number of empty cases (not limited to 3 cases as in the first move).

2. It means the player for which it is the turn to play has a winning move by moving his pawn to row G, on column 2. In the example, it was the second test case, so it was white's turn to play. Note that columns start from 1, not from 0.

3. White always plays the first move in the game, however it is not relevant in this puzzle since you are given which player's turn it is to play (see input specifications 2.a)

Good luck !

[Moises Lopez]

I have the same problem as allways
My program gives the correct answer in the first and last test but fails in the rest. So ther ie a tiny error that only happens in same cases. ¿Any idea for testing that cases?

[code_excalibur]

What do we mean by the move garantees a win in the future if you always play perfectly. Moreover when does a player win??

[random.johnnyh]

What does "Pawns cannot only move vertically (in both directions)" mean?

[hellocopter]

should be "Pawns can only move vertically (in both directions)"

[admin]

@random.johnnyh, @hellocopter
Thanks typo fixed.

@code_excalibur
A player wins when the other player cannot move anymore (e.g. all his pawns are pinned to the row where they started from). A move can guarantee a win in this game, since it can be proven that if you play perfectly (keep on doing winning moves) from a winning position then you will win.

For example, if you play the little game on the puzzle page with 4 columns and start with color black, you can always win by
1. always moving forward (towards the opponent)
2. maintaining the exact same distance between the pawns on columns 1 and 2 and independently maintaining the same distance on columns 3 and 4. (e.g. if the A.I. moves 2 cases down on column 1, you move 2 cases up on column 2, and so on).

[Shotaro Yamazoe]

If I have black pawns and there is a winning strategy, then what should I print?
My winning move depend on opponent's first move.

Please clarify.

[admin]

If I have black pawns and there is a winning strategy, then what should I print?
My winning move depend on opponent's first move.

Please clarify.

You are given an in-game position, and you are also given what player turn it is to play. In any case, it's always your turn to play, either as black or white.

For example in the test case, below, the first test you are playing as black and it is your turn to play, for the second test you are playing as white and it is your turn to play.

Code: Select all

2
B 3
W ACB
B CEC
W 3
W AAF
B CHH

Hope it clarifies !