37 lines
522 B
Ruby
37 lines
522 B
Ruby
|
#!/usr/bin/env ruby
|
||
|
|
# Ruby version of a Prime Number Finder
|
||
|
|
# haplo@mindstab.net
|
||
|
|
|
||
|
|
include Math
|
||
|
|
|
||
|
|
class Primes
|
||
|
|
def findPrimes(cmax)
|
||
|
|
3.step(cmax,2) { |i|
|
||
|
|
max = sqrt(i)
|
||
|
|
isPrime = 1
|
||
|
|
3.step(max, 2) { |x|
|
||
|
|
isPrime = i % x
|
||
|
|
if isPrime == 0
|
||
|
|
break
|
||
|
|
end
|
||
|
|
}
|
||
|
|
if isPrime != 0
|
||
|
|
print i, "\n"
|
||
|
|
end
|
||
|
|
}
|
||
|
|
end
|
||
|
|
end
|
||
|
|
|
||
|
|
|
||
|
|
MAX = ARGV[0].to_i;
|
||
|
|
if ! MAX
|
||
|
|
print "primes.rb <MAX NUM>\n"
|
||
|
|
exit(1)
|
||
|
|
elsif MAX < 1
|
||
|
|
print "Invalid MAX Input\n"
|
||
|
|
exit(1)
|
||
|
|
end
|
||
|
|
|
||
|
|
prime = Primes.new();
|
||
|
|
prime.findPrimes(MAX);
|