Project Euler Problem 2 Solution

Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:

1, 2, 3, 5, 8, 13, 21, 34, 55, 89, …

Find the sum of all the even-valued terms in the sequence which do not exceed four million.

My solution in Ruby:

t1, t2, even_sums = 1, 2, 2
loop do
  temp = t1 + t2
  break if temp > 3999999
  even_sums += temp if temp % 2 == 0
  t1 = t2
  t2 = temp
end

puts even_sums

Project Euler Problem 1 Solution

If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.

Find the sum of all the multiples of 3 or 5 below 1000.

My solution in Ruby:

sum = 0
for i in 1..999
  sum += i if i % 3 == 0 or i % 5 == 0
end

puts sum