http://www.codinghorror.com/blog/archives/000781.html
It is about how a lot of job applicants have a hard time actually programming. My friend and I were amused by it and started going back and forth with different implementations until it got to this point.
The problem is:
'Write a program that prints the numbers from 1 to 100. But for multiples of three print "Fizz" instead of the number and for the multiples of five print "Buzz". For numbers which are multiples of both three and five print "FizzBuzz".'
Now, it can be done like this:
1.upto(100) { |n| puts n % 3 == 0 ? n % 5 == 0 ? "fizzbuzz" : "buzz" : n % 5 == 0 ? "fizz" : n }
But, this is what I ended up with, which turns out actually to be faster and obviously far more flexible:
class FizzBuzz def initialize(start_number, end_number) @starting = start_number @ending = end_number @phrase_multiples = [] end def add_phrase_multiple(phrase, multiple) @phrase_multiples << [phrase, multiple] end def print_phrases fb_array = process_phrases puts fb_array.collect { |e| e[1] || e[0] }.join("\n") end private def process_phrases rarray = Array.new(@ending - @starting) rarray = rarray.each_with_index { |item, i| rarray[i] = [i + @starting, item] } @phrase_multiples.each { |pm| fill_multiples(rarray, pm[1], pm[0]) } rarray end def fill_multiples(fill_array, the_int, printed) (the_int - (fill_array[0][0] % the_int)).step(fill_array.size - 1, the_int) do |i| fill_array[i][1] = fill_array[i][1].to_s + printed.to_s end end end fb = FizzBuzz.new(1,100) fb.add_phrase_multiple('fizz', 3) fb.add_phrase_multiple('buzz', 5) fb.print_phrases