--- /dev/null
+The 8-queens problem
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++--------+
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++--------+
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++--------+
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++--------+
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++--------+
+|..Q.....|
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+|...Q....|
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++--------+
++--------+
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+|.Q......|
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++--------+
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+|.Q......|
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+|..Q.....|
+|....Q...|
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+|...Q....|
++--------+
++--------+
+|.Q......|
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+|.....Q..|
+|..Q.....|
++--------+
++--------+
+|.Q......|
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+|.......Q|
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+|Q.......|
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++--------+
++--------+
+|.Q......|
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+|Q.......|
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+|......Q.|
+|....Q...|
++--------+
++--------+
+|.Q......|
+|.....Q..|
+|Q.......|
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+|...Q....|
+|.......Q|
+|..Q.....|
+|....Q...|
++--------+
++--------+
+|.Q......|
+|....Q...|
+|......Q.|
+|...Q....|
+|Q.......|
+|.......Q|
+|.....Q..|
+|..Q.....|
++--------+
++--------+
+|.Q......|
+|....Q...|
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+|Q.......|
+|..Q.....|
+|.......Q|
+|.....Q..|
+|...Q....|
++--------+
++--------+
+|.Q......|
+|...Q....|
+|.....Q..|
+|.......Q|
+|..Q.....|
+|Q.......|
+|......Q.|
+|....Q...|
++--------+
++--------+
+|Q.......|
+|......Q.|
+|....Q...|
+|.......Q|
+|.Q......|
+|...Q....|
+|.....Q..|
+|..Q.....|
++--------+
++--------+
+|Q.......|
+|......Q.|
+|...Q....|
+|.....Q..|
+|.......Q|
+|.Q......|
+|....Q...|
+|..Q.....|
++--------+
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+|Q.......|
+|.....Q..|
+|.......Q|
+|..Q.....|
+|......Q.|
+|...Q....|
+|.Q......|
+|....Q...|
++--------+
++--------+
+|Q.......|
+|....Q...|
+|.......Q|
+|.....Q..|
+|..Q.....|
+|......Q.|
+|.Q......|
+|...Q....|
++--------+
+Found 92 solutions