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Can you tile a chessboard with two missing squares?
How many queens and knights can you place on a chessboard?
In how many ways can you place 8 queens on a chessboard?
Alice and Bob sit down, face to face, with a chessboard in front of them. They are going to play a little game, but this game only has a single knight... Who will win?
⎕←⎕ucs 2∘⊥∘⌽¨ ↓7 (⊢⍴⍨⊣,⍨÷⍨∘≢) ⍎¨ '0001011001011100101110000111110', '0111010111011110101111010101101', '1100001100101110001011110011100', '0011100001110111010110001111110111011011'