Project Euler: Problem 19 in Ruby

Although it felt dirty, I used Ruby’s baked-in date class. I’d written some day-of-week code when I first started coding, before I knew better, and it’s annoying. Besides, this was my last problem to do before level 1. That’s right…

LEVEL 1!!!!

Bravo, thejoezack! Now that you have solved 25 problems you have achieved what 79.52% of members have failed to do and have advanced to level 1. Good luck as you continue.”

I’m proud. I found a few of the problems to be really hard and it feels really good to have finally hit a milestone. I’ve actually had a much easier time with the problems as I’ve gone on, as I’ve learned a lot about solving these problems and perhaps even problem solving in general. Kudos and thanks, Project Euler!

Oh yeah…and here’s my solution:

Problem #19

How many Sundays fell on the first of the month during the twentieth century (1 Jan 1901 to 31 Dec 2000)?

require 'date'

start = 1901, 1, 1
total = 0

(100 * 12 - 1).times do |i|
  total += 1 if (start >> i).wday == 0

puts total