RosettaCodeData/Task/Primality-by-trial-division/Ruby/primality-by-trial-division-1.rb
2015-11-18 06:14:39 +00:00

11 lines
200 B
Ruby

def prime(a)
if a == 2
true
elsif a <= 1 || a % 2 == 0
false
else
divisors = (3..Math.sqrt(a)).step(2)
divisors.none? { |d| a % d == 0 }
end
end
p (1..50).select{|i| prime(i)}