Euler Project Problem #010

euler10.rb

# Solution to Project Euler's tenth problem
# http://projecteuler.net/index.php?section=problems&id=10
# Find the sum of all primes below two million.
def generate_primes(ceiling)
	primes, count = [1, 2], 1
	until primes.last > ceiling do
		numbers = (primes[count-1]**2+1..primes[count]**2).to_a
		1.upto(count) {|c| numbers.select! {|number| number%primes[c] != 0}}
		primes.concat(numbers)
		count += 1
	end
	primes.shift #remove 1
	return primes
end
def sum_primes(primes, ceiling)
	sum = 0
	primes.each do |p|
		if p < ceiling then
			sum = sum + p
		else
			return sum
		end
	end
end

number = 2000000
primes = generate_primes(number)
sum = sum_primes(primes, number)
puts sum