Different solutions for Fizz Buzz in Ruby

fizzbuzz.rb

def fizz_buzz_1(max)
  arr = []
  (1..max).each do |n|
    if ((n % 3 == 0) && (n % 5 == 0))
      arr << "FizzBuzz"
    elsif (n % 3 == 0)
      arr << "Fizz"
    elsif (n % 5 == 0)
      arr << "Buzz"
    else
      arr << n
    end
  end
  return arr
end

def fizz_buzz_2(max)
  arr = []
  (1..max).each do |n|
    if (n % 3 == 0)
      if (n % 5 == 0)
        arr << "FizzBuzz"
      else
        arr << "Fizz"
      end
    elsif (n % 5 == 0)
      arr << "Buzz"
    else
      arr << n
    end
  end
  return arr
end

def fizz_buzz_3(max)
  arr = []
  (1..max).each do |n|
    text = ""
    if (n % 3 == 0)
      text << "Fizz"
    end
    if (n % 5 == 0)
      text << "Buzz"
    end
    if !((n % 3 == 0) || (n % 5 == 0))
      text = n
    end
    arr << text
  end
  return arr
end

Another one liner, courtesy of Eno Compton

puts (1..100).map { |i| (fb = [["Fizz"][i % 3], ["Buzz"][i % 5]].compact.join).empty? ? i : fb }

(1..100).each do |i|
    c1 = (i % 5 == 0) ? "Buzz" : nil
    c2 = (i % 3 == 0) ? "Fizz" : nil
    puts (!c1 && !c2) ? i : ((c2 || "") + (c1 || ""))
end

I did a version of this using Ruby and RSpec. The code is printed at the bottom. The following 2 links show the process of writing this code, since TDD is all about process :)

Video: http://bit.ly/FizzBuzz_TDD

Slideshare: http://www.slideshare.net/jordanpoulton/intro-to-ruby-and-testdriven-development-fizzbuzz-kata-by-makers-academy

And here, the code:

~/spec/fizzbuzz_spec.rb:

require 'fizzbuzz'

describe 'FizzBuzz' do
  context 'knows that a number is divisible by' do
    it '3' do
      expect(is_divisible_by_three?(3)).to be_true
    end
    it '5' do
      expect(is_divisible_by_five?(5)).to be_true
    end
    it '15' do
      expect(is_divisible_by_fifteen?(15)).to be_true
    end
  end


  context 'knows that a number is not divisible by' do
    it '3' do
      expect(is_divisible_by_three?(1)).not_to be_true
    end
    it '5' do
      expect(is_divisible_by_five?(1)).not_to be_true
    end
    it '15' do
      expect(is_divisible_by_fifteen?(1)).not_to be_true
    end
  end

  context 'while playing the game it returns' do
    it 'the number' do
      expect(fizzbuzz(1)).to eq 1
    end
    it 'Fizz' do
      expect(fizzbuzz(3)).to eq "Fizz"
    end
    it 'Buzz' do
      expect(fizzbuzz(5)).to eq "Buzz"
    end
    it "FizzBuzz" do
      expect(fizzbuzz(15)).to eq "FizzBuzz"
    end
  end
end

~/lib/fizzbuzz.rb

def fizzbuzz(number)
  return "FizzBuzz" if is_divisible_by_fifteen?(number)
  return "Buzz" if is_divisible_by_five?(number)
  return "Fizz" if is_divisible_by_three?(number)
  number
end

def is_divisible_by_three?(number)
  is_divisible_by(number, 3)
end

def is_divisible_by_five?(number)
  is_divisible_by(number, 5)
end

def is_divisible_by_fifteen?(number)
  is_divisible_by(number, 15)
end

def is_divisible_by(number, divisor)
  number % divisor == 0
end

fizzbomb= Proc.new do |n|
if n % 5 == 0 && n % 3 == 0
puts "fizzbuzz"
elsif n % 3 == 0
puts "fizz"
elsif n % 5 == 0
puts "bomb"
else
puts n
end
end
puts "pick a number"
number= Integer(gets.chomp)
(1..number).to_a.select(&fizzbomb)

(1..42).each do | n, fb |
fb = fb.to_s + "Fizz" if n%3==0
fb = fb.to_s + "Buzz" if n%5==0
puts fb || n
end

A little too much fun with FizzBuzz...

module FunFizzBuzz

  class ModResult
    include Comparable
    attr_accessor :mod, :result_proc

    def initialize(mod, result_proc)
      self.mod = mod
      self.result_proc = result_proc
    end

    def <=> other
      self.mod <=> other.mod
    end

  end

  class Sequencer
    attr_accessor :max

    def initialize(max)
      self.max = max
    end

    def sequence(mod_procs)
      mps = mod_procs.sort.reverse # need to test biggest divisors first
      (1..self.max).each do |i|
        mp_found = mps.detect { |mp| i % mp.mod == 0 }
        puts mp_found ? mp_found.result_proc.call(i) : block_given? ? yield(i) : i 
      end
    end

  end

end

s = FunFizzBuzz::Sequencer.new(100)
mps = [FunFizzBuzz::ModResult.new(3, Proc.new { |i| "Fizz" }), FunFizzBuzz::ModResult.new(5, Proc.new { |i| "Buzz" }), FunFizzBuzz::ModResult.new(15, Proc.new { |i| "FizzBuzz" })]
s.sequence(mps)

mps = [FunFizzBuzz::ModResult.new(2, Proc.new { |i| "FizzNew #{i}" }), FunFizzBuzz::ModResult.new(3, Proc.new { |i| "BuzzNew #{i}" }), FunFizzBuzz::ModResult.new(6, Proc.new { |i| "FizzBuzzNew #{i}" })]
s.sequence(mps)

+1 for @jordanpoulton's approach/solution.

1.step(100,1) do |i|
    if (i % 5) == 0 && (i % 3) ==0
        puts 'FizzBuzz'
    elsif (i % 5) == 0
        puts 'Buzz'
    elsif (i % 3) == 0
        puts 'Fizz'
    else
        puts i
    end
end

NAMED_FACTORS = {
  3 => 'Fizz',
  5 => 'Buzz'
}

def evenly_divides?(numerator, denominator)
  numerator % denominator == 0
end

def named_factors(number)
  NAMED_FACTORS.map do |factor, name|
    name if evenly_divides?(number, factor)
  end.compact
end

def transform(range)
  range.map do |number|
    names = named_factors(number)
    names.any? ? names.join : number
  end
end

transform(1..100)

Poor man's pattern matching:

fizzbuzz =
  (1..100).map do |n|
    case [n % 3, n % 5].map(&:zero?)
    when [true, true]
      "FizzBuzz"
    when [true, false]
      "Fizz"
    when [false, true]
      "Buzz"
    else
      n
    end
  end
puts fizzbuzz

What I like about this approach is that you avoid the duplicate n % x == 0 conditions that are necessary in the if else version without having to resort to i % 15 which always seemed hacky to me, without going too crazy like many of the purely un-conditional fizzbuzzes out there.

How many times has this problem been solved already? Idiomatic Ruby embraces the DRY principle. Not just in your own code base, but the entire internet.

require 'curb'
require 'nokogiri'

class Dry

  # Why copy & paste answers from stack overflow when you can curl & eval them!
  # Expects a url#answer-id and a hash of adjustments to the answer code to gsub over
  def self.fuck_it_just_copy_something_from_stackoverflow(url, adjustments)
    # build the adjustment lambda
    edit = "lambda { |method_string| method_string"
    adjustments.each { |k,v| edit += ".gsub('#{k}', '#{v}')" }
    edit += "}"

    # then get some of that overflow goodness
    answer = url.split('#').last
    @doc ||= Nokogiri::HTML Curl.get(url).body_str
    @doc.css("#answer-#{answer} code").each do |code|
      # Oh yeah, it's lambda time! Eval the edit string, pass it the overflow code and eval the resulting lambda
      return eval eval(edit).call code.content
    end
  end
end

100.times do |number|
  url = 'http://stackoverflow.com/questions/24435547/ruby-fizzbuzz-not-working-as-expected#24435693'
  adjustments = {'puts' => 'return', 'def fizzbuzz(n)' => 'lambda do |n|'}
  p Dry.fuck_it_just_copy_something_from_stackoverflow(url, adjustments).call(number).last.to_s
end

I really like this solution from reddit:

a=b=c=(1..100).each do |num|
  print num, ?\r,
    ("Fizz" unless (a = !a) .. (a = !a)),
    ("Buzz" unless (b = !b) ... !((c = !c) .. (c = !c))),
    ?\n
end

fizz_buzz =
    (1..100).map do |i|
        case
        when i % 15 == 0 then "FizzBuzz"
        when i % 3 == 0 then "Fizz"
        when i % 5 == 0 then "Buzz"
        else i
        end
    end
puts fizz_buzz

low=1
high=100
      (low..high).each {|x|
       puts x%15==0?'FizzBuzz':x%5==0?'Buzz':x%3==0?'Fizz':x
      }

_=$$/$$;__=_-_;@_=_+_;$_=@_+_;$__=@_+$_;$-_=$__*$_;@__=''<<$-_*($__+$_)+@_;$___=''<<$-_*$__-$__<<$-_*($__+@_)<<@__<<@__;@___=''<<$-_*$__-$_*$_<<$-_*($__+$_)-$_<<@__<<@__;(___=->{$.+=_;$><<($.%$-_==__ ?$___+@___:$.%$_==__ ?$___:$.%$__==__ ?@___:$.)<<(''<<$__*@_);$.<($__*@_)**@_?___[]:_})[]

Thanks to http://threeifbywhiskey.github.io/2014/03/05/non-alphanumeric-ruby-for-fun-and-not-much-else/

(1..100).each do |x|
  fizz = "Fizz" if (x % 3 == 0)
  buzz = "Buzz" if (x % 5 == 0)
  puts (fizz || buzz) ? fizz.to_s + buzz.to_s : x
end

class Fixnum
  def to_s
    string = ''
    string += 'fizz' if self % 3 == 0
    string += 'buzz' if self % 5 == 0
    return string unless string.empty?
    inspect
  end
end

puts (1..100).to_a

(1..100).each do |i|
if i % 5 == 0 && i % 3 == 0
puts 'FizzBuzz'
elsif i % 5 == 0
puts 'Buzz'
elsif i % 3 == 0
puts 'Fizz'
else
puts i
end

end

#FizzBuzz

(1..100).each do |number|
if (number % 3 == 0) and (number % 5 != 0)
puts "Fizz"
elsif (number % 5 == 0 ) and (number % 3 != 0)
puts "Buzz"
elsif (number % 5 == 0) and (number % 3 == 0)
puts "FizzBuzz"
else
puts number
end
end

buzzer = lambda do |i|
  map = {ff: i, tf: 'Fizz', ft: 'Buzz', tt: 'FizzBuzz'}
  map[((i%3==0).to_s[0] + (i%5==0).to_s[0]).to_sym]
end
puts (1..100).map(&buzzer)

(0..100).map{|i|i%15==0?'FizzBuzz':i%3==0?'Fizz':i%5==0?'Buzz':i}

#66 chars :)

This one requires presence from Rails (i.e., it works in rails console):

puts 1.upto(100).map { |n| "#{'Fizz' if n%3==0}#{'Buzz' if n%5==0}".presence || n }

(1..100).map{|n|({3=>['Fizz'],5=>['Buzz']}.map{|x,y|y[n%x]}.join.gsub(/^$/,n.to_s))}

@willwright82 's solution modified for less == 0:

(1..100).map do |m|
  case 0
  when m % 15 then 'FizzBuzz'
  when m % 3  then 'Fizz'
  when m % 5  then 'Buzz'
  else m
  end
end

def fizzbuzz(int)
if int % 3 == 0 && int % 5 == 0
"FizzBuzz"
elsif int % 3 == 0
"Fizz"
elsif int % 5 == 0
"Buzz"
else int % 4 == 0
nil
end
end

70 characters

(1..100).map{|x|puts x%15==0?'FizzBuzz':x%5==0?'Buzz':x%3==0?'Fizz':x}

When I thought we already had way too many solutions... !

module BeingMultiple
  refine Integer do
    def eitherFizzOrBuzz!
      return "FizzBuzz" if multiple?(3) && multiple?(5)
      return "Fizz" if multiple?(3)
      return "Buzz" if multiple?(5)
      self
    end
    
    private
    
    def multiple?(target)
      self % target == 0
    end
  end
end

using BeingMultiple

puts (1..n).map(&:eitherFizzOrBuzz!).join("\n")

require "fizzbuzz"

RSpec.describe FizzBuzz do
  describe "#compute" do
    context "when number is dvisisble by 3" do
      it "returns fizz" do
        expect(FizzBuzz.compute(6)).to eq("fizz")
      end
    end

    context "when number is dvisisble by 5" do
      it "returns buzz" do
        expect(FizzBuzz.compute(10)).to eq("buzz")
      end
    end

    context "when number is dvisisble by both 3 and 5" do
      it "returns buzz" do
        expect(FizzBuzz.compute(15)).to eq("fizzbuzz")
      end
    end
  end
end


class FizzBuzz
  def self.compute(number)
    return "fizzbuzz" if (number % 15).zero?

    if (number % 3).zero? "fizz" else "buzz" end
  end
end