Brain Teasers
The Eight Queens
One of the most famous logic puzzles is the "Eight Queens puzzle". The object of this puzzle is to place 8 chess queens on a standard 8x8 chessboard so that no queen can be captured by any of the other queens.
Logically, no queen can share the same row, column, or diagonal with any other queen.
Can you discover an arrangement that works?
Logically, no queen can share the same row, column, or diagonal with any other queen.
Can you discover an arrangement that works?
Answer
There are actually 12 completely unique solutions to this puzzle (unique meaning not simply rotating or flipping the board).Using a standard system of numbering rows 1-8 moving away from the player and noting columns with letters a-h, here are the solutions:
1) a1, g2, e3, h4, b5, d6, f7, c8
2) a1, g2, d3, f4, h5, b6, e7, c8
3) c1, a2, g3, e4, h5, b6, d7, f8
4) d1, a2, e3, h4, b5, g6, c7, f8
5) e1, a2, h3, d4, b5, g6, c7, f8
6) e1, a2, d3, f4, h5, b6, g7, c8
7) e1, a2, h3, f4, c5, g6, b7, d8
8) e1, c2, a3, g4, b5, h6, f7, d8
9) e1, g2, a3, d4, b5, h6, f7, c8
10) f1, a2, e3, b4, h5, c6, g7, d8
11) f1, c2, a3, h4, d5, b6, g7, e8
12) g1, a2, c3, h4, f5, d6, b7, e8
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Comments
that was easy with a chess board.but this is not fair for those who never play chess before.
nice one...have seen that before...but never knew it had 12 unique solutions...thanks keep it up!
lol the answer to the question is yes
There was a game on Yahoo that tested your ability to place eight pieces on the chess board.
What about: h1, f2, d3, b4, g5, e6, c7, a8?
I got a1 b5 c2 d6 e3 f7 g4 h8, it's not in any of the 12 answers stated but I don't see why this doesn't work! I don't play chess so if any chess player would like to enlighten me that would be awesome.
I got a1 b5 c2 d6 e3 f7 g4 h8, it's not in any of the 12 answers stated but I don't see why this doesn't work! I don't play chess so if any chess player would like to enlighten me that would be awesome.
@grace317, the one you put in A1 would hit the one in H8.
@DarthKaan, those would all hit each other diagonally.
I have one not listed there.
With columns A-H being left to right and rows 1-8 being top to bottom:
F1
H2
B3
D4
A5
G6
E7
C8
Or with columns A-H being left to right and rows 1-8 being bottom to top (standard system of numbering rows 1-8 moving away from the player):
C1
E2
G3
A4
D5
B6
H7
F8
Looks like this:
XXXXXOXX
XXXXXXXO
XOXXXXXX
XXXOXXXX
OXXXXXXX
XXXXXXOX
XXXXOXXX
XXOXXXXX
With columns A-H being left to right and rows 1-8 being top to bottom:
F1
H2
B3
D4
A5
G6
E7
C8
Or with columns A-H being left to right and rows 1-8 being bottom to top (standard system of numbering rows 1-8 moving away from the player):
C1
E2
G3
A4
D5
B6
H7
F8
Looks like this:
XXXXXOXX
XXXXXXXO
XOXXXXXX
XXXOXXXX
OXXXXXXX
XXXXXXOX
XXXXOXXX
XXOXXXXX
Never mind, I see it's a rotation of sequence #3
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