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@gavinmyers
Created May 14, 2012 02:11
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Prime Number Calculator in Ruby
#!/usr/bin/env ruby
puts "limit number:"
max = Integer(gets)
primes = []
puts "going from 2 to #{max}"
(2..max).select do |current|
# if current is divisible by any number in the array (that is not itself) it is not prime
isPrime = true
primes.each do |prime|
md = current % prime
if md == 0 then isPrime = false end
end
if isPrime then primes << current end
end
primes.each do |prime|
puts prime
end
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