39 lines
750 B
Ruby
39 lines
750 B
Ruby
# The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.
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#
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# Find the sum of all the primes below two million.
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class NthPrime
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def initialize
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@t=[]
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end
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def is_prime(n)
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@t.each do |x|
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return false if n % x == 0
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end
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return true
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end
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def genPrimeUpTo(x)
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i=2
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while i<x
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if is_prime(i)
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@t<<=i
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# puts %{#{i} [#{@t.length}]}
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end
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i+=1
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end
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return @t
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end
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def sumOfPrimeUpTo(x)
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@t=[];
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genPrimeUpTo(x)
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sum=0
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@t.each do |n|
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sum+=n
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end
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return sum
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end
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end
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prime_finder=NthPrime.new
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puts prime_finder.sumOfPrimeUpTo(2000000)
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