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astronomy88/sieve_nomod.rb

Last active August 29, 2015 13:57
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sieve_nomod.rb
end_value = 120
#-- Without using mod
b = Array(2..end_value)
primes = Array(2..end_value)
limit = Math.sqrt end_value
b.each do |z|
break if z >= limit
primes.each do |i|
break if (z*i) > b.last
next if i == 0
primes[(z*i)-2] = 0 if primes[(z*i)-2] == (z * i)
end
end
primes.delete_if { |j| j == 0 }
puts "Sieve of erastothenes: #{primes}"
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