25 lines
593 B
Ruby
25 lines
593 B
Ruby
descr=%{
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An irrational decimal fraction is created by concatenating the positive integers:
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0.123456789101112131415161718192021...
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It can be seen that the 12^(th) digit of the fractional part is 1.
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If d_(n) represents the n^(th) digit of the fractional part, find the value of the following expression.
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d_(1) × d_(10) × d_(100) × d_(1000) × d_(10000) × d_(100000) × d_(1000000)
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}
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str=""
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(1..(1000000)).each do |i|
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str.concat(i.to_s)
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end
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prod=1
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(0..6).each do |p|
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digit=str[10**p - 1]-"0"[0]
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puts digit
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prod *= digit
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end
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puts "Product = #{prod}"
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