Project Euler 29: Ruby

In my attempt to learn Ruby out in the open, here’s my solution for Project Euler Problem 29. 

I have provided a straight-forward, brute force solution to the problem below. Though the question talks about ordering the terms numerically, there’s no reason to do so. The only thing you need be concerned with is the number of distinct terms. If I were solving this problem in C#, I might leverage the C# HashSet to gather the terms. But I’m still focused on Ruby and it didn’t take long to hunt down the Ruby Set class.

As always, any feedback is welcome.

# Euler 29
# http://projecteuler.net/index.php?section=problems&id=29
# Consider all integer combinations of ab for 2 <= a <= 5
# and 2 <= b <= 5:
#
# 2^2=4, 2^3=8, 2^4=16, 2^5=32
# 3^2=9, 3^3=27, 3^4=81, 3^5=243
# 4^2=16, 4^3=64, 4^4=256, 4^5=1024
# 5^2=25, 5^3=125, 5^4=625, 5^5=3125
#
# If they are then placed in numerical order, with any
# repeats removed, we get the following sequence of 15
# distinct terms:
#
# 4, 8, 9, 16, 25, 27, 32, 64, 81, 125, 243, 256, 625, 1024, 3125
#
# How many distinct terms are in the sequence generated by ab
# for 2 <= a <= 100 and 2 <= b <= 100?
timer_start = Time.now

require 'set'
distinct_terms = Set.new

(2..100).each do |a|
  (2..100).each do |b|
    distinct_terms << a**b
  end
end

puts distinct_terms.length
puts "Elapsed Time: #{(Time.now - timer_start)*1000} milliseconds"