22 lines
421 B
Ruby
22 lines
421 B
Ruby
# This solution cheats and uses only one generator!
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def powers(m)
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return enum_for(:powers, m) unless block_given?
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n = 0
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loop { yield n ** m; n += 1 }
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end
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def squares_without_cubes
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return enum_for(:squares_without_cubes) unless block_given?
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cubes = powers(3)
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c = cubes.next
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powers(2) do |s|
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(c = cubes.next) until c >= s
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yield s unless c == s
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end
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end
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p squares_without_cubes.take(30).drop(20)
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