53 lines
1.2 KiB
Ruby
53 lines
1.2 KiB
Ruby
#!/usr/bin/ruby
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# get_primes.rb
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=begin
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This file is part of the ARM-Crypto-Lib.
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Copyright (C) 2008 Daniel Otte (daniel.otte@rub.de)
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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=end
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$primes = [2,3,5]
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def check_prime(a)
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q = Math.sqrt(a)
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$primes.each{ |p|
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return true if p>q
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return false if a%p==0
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}
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return true
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end
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def find_primes(n)
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a = $primes.last+2
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while $primes.size < n
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if check_prime(a)
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$primes << a
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end
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a += 2
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end
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end
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if ARGV.size!=1
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STDERR.print <<EOF
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Usage: ruby #{$0} n
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EOF
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exit(1)
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end
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find_primes(ARGV[0].to_i);
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print($primes.join(', '))
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puts("")
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