Learning some Ruby

00_learn_ruby.md

Aprende a Programar con Ruby

01_numbers.rb

puts 365 * 24 # how many hours are in a year?
puts 10 * 365 * 24 * 60 # how many minutes are in a decade?
puts 30 * 365 * 24 * 60 * 60 # how many seconds old are you? (30 years)
puts 1031000000 / 60 / 60 / 24 / 365 # how many years do I have, if I'm 1031 million seconds old?

02_hello_full_name.rb

print "What's your first name?"
first_name = gets.chomp
print "What's your middle name?"
middle_name = gets.chomp
print "What's your last name?"
last_name = gets.chomp

puts "Hi there, #{first_name} #{middle_name} #{last_name}!"

03_enhance_fav_number.rb

print "What's your favorite number?"
fav_number = gets.chomp.to_i + 1

puts "Well, your new favorite number can be #{fav_number}, don't you think?"
puts "It's a better and enhanced number. :)"

04_angry_boss.rb

puts "AND NOW WHAT DO YOU WANT!?!?"

answer = gets.chomp.upcase

puts "WHY WOULD YOU SAY THAT? \"#{answer}\"?!? YOU'RE FIRED!!"

05_align_strings.rb

lineWidth = 52

puts 'Table of Contents'.center lineWidth
puts 
puts 'Chapter 1:  Numbers'.ljust(lineWidth/2) + 'page 1'.rjust(lineWidth/2)
puts 'Chapter 2:  Strings'.ljust(lineWidth/2) + 'page 72'.rjust(lineWidth/2)
puts 'Chapter 3:  Variables'.ljust(lineWidth/2) + 'page 118'.rjust(lineWidth/2)

06_99_bottles_of_beer_on_the_wall.rb

bottles = 99

while bottles > 1
  puts "#{bottles} bottles of beer on the wall, #{bottles} bottles of beer."
  bottles = bottles - 1 # removes 1 bottle

  if bottles > 1
    puts "Take one down, pass it around, #{bottles} bottles of beer on the wall..."
  else
    puts "Take one down, pass it around, 1 bottle of beer on the wall..."
  end

  puts ""
end

puts "If that one bottle should happen to fall, what a waste of alcohol!"

07_deaf_grandma.rb

total_bye = 1
message = ''

while message != 'GOODBYE' or total_bye < 3
  if !message.empty?
    if message == message.upcase and message != 'GOODBYE'
      # mostrar un año entre 1930 y 1950
      year = 1930 + rand(20)
      puts "NO, NOT SINCE #{year}!"
      # resetear la cantidad de saludos
      total_bye = 1
    else
      if(total_bye < 3)
        puts "HUH?! TALK LOWDER, SON!"

        if message == 'GOODBYE'
          total_bye = total_bye + 1 # user has to say GOODBYE 3 times to exit the program
        end
      end
    end
  else
    puts "HELLO SONNY, HOW ARE YOU?"
  end

  message = gets.chomp
end

puts "GOODBYE. I'LL MISS YOU!"

08_leap_years.rb

print "Start year:"
start_year = gets.chomp.to_i
print "End year:"
end_year = gets.chomp.to_i

if start_year >= end_year
  puts "The start year must be earlier than the end year."
else
  current_year = start_year

  while current_year <= end_year
    if current_year % 4 == 0
      if current_year % 100 == 0
        if current_year % 400 == 0
          puts current_year
        end
      else
        puts current_year
      end
    end

    current_year = current_year + 1
  end
end

09_add_sort_words.rb

puts "Start writing random words."
puts "When you want to stop, just press Enter without any content."
puts

words = []

message = gets.chomp
words.push message

while message.length > 0
  message = gets.chomp
  if !message.empty?
    words.push message
  end
end

puts words.sort

10_add_sort_words_without_sort.rb

puts "Start writing random words."
puts "When you want to stop, just press Enter without any content."
puts

words = []
sorted_words = []

message = gets.chomp
words.push message

while message.length > 0
  message = gets.chomp
  if !message.empty?
    words.push message
  end
end

while !words.empty?
  sorted_words.push words.delete(words.min)
end

puts sorted_words

11_sort_without_sort.rb

array = [4, 1, 3, 2, 5, 6]
sorted = []

while !array.empty?
  sorted.push array.delete(array.min)
end

puts sorted

12_contents_table_array.rb

lineWidth = 52

contents = []
contents.push ['Chapter 1:  Numbers', 'page 1']
contents.push ['Chapter 2:  Strings', 'page 72']
contents.push ['Chapter 3:  Variables', 'page 118']

puts 'Table of Contents'.center lineWidth
puts 

contents.each do |content|
  puts content[0].ljust(lineWidth/2) + content[1].rjust(lineWidth/2)
end

13_birthday_seconds.rb

now = Time.new
birthday = Time.mktime(1984, 2, 6, 12)

difference = now.to_i - birthday.to_i
puts "#{difference} seconds has passed since I was born"

million_secs = birthday + 1000000000
puts "At #{million_secs} I'll be a billion seconds old. :)"

14_happy_spanking.rb

puts "What is the year you were born?"
year = gets.chomp.to_i
puts "What is the month you were born?"
month = gets.chomp.to_i
puts "What is the day you were born?"
day = gets.chomp.to_i

birthday = Time.mktime(year, month, day)
now = Time.now

difference = now - birthday
years = difference.to_i / 60 / 60 / 24 / 365

puts "SPANK!\n" * years # user receives a spank for each birthday

15_dice.rb

class Dice

  def initialize
      roll
  end

  def roll
    @numeroMostrado = 1 + rand(6)
  end

  def show
    @numeroMostrado
  end

  def cheat num = 0
    if num >= 1 and num <= 6
      num
    else
      "If you're going to cheat, at least use a number between 1 and 6."
    end
  end

end

dice = Dice.new

puts dice.roll
puts
puts dice.show
puts
puts dice.cheat 5

16_orange_tree.rb

class OrangeTree
  def initialize
    @totalOranges = 0
    @height = 0
    @age = 0
  end

  def height
    @height
  end

  def passingOf365Days
    @age = @age + 1
    if @age > 100
      puts "The orange tree has died. :("
      exit
    end

    if @height == 0
      @height = 1
    else
      @height = @height * 2
    end

    # when a year passes, oranges that were not collected, fall
    @totalOranges = 0

    # the tree should produce oranges from reaching 5 years of age
    if @age >= 5
      @totalOranges = @age
    end
  end

  def countOranges
    @totalOranges
  end

  def pickAnOrange
    if @totalOranges > 0
      @totalOranges = @totalOranges - 1
      puts "That orange was delicious!"
    else
      puts "There are no more oranges to pick this year."
    end
  end
end

tree = OrangeTree.new

tree.passingOf365Days
tree.passingOf365Days
tree.passingOf365Days
puts tree.height
tree.passingOf365Days
puts tree.height
tree.passingOf365Days
puts tree.height

puts tree.countOranges
tree.pickAnOrange
tree.pickAnOrange
tree.pickAnOrange
tree.pickAnOrange
tree.pickAnOrange
tree.pickAnOrange
tree.pickAnOrange

tree.passingOf365Days
puts tree.countOranges
puts tree.height

17_grandpa_clock.rb

def makeBong
  hours = Time.now.hour
  if hours > 12
    hours - 12
  end

  hours.times do
    yield
  end
end

# this is a block that is being passed to a method
# to use its code as many times as the method wants to
makeBong do
  puts 'BONG!'
end

18_bank_loan.rb

# types of clients / percentages to apply
client_a = 4
client_b = 9
client_c = 12

# init variables
loan = 100
months_to_return = 3
selected_client = client_b
# end init

time_passed = months_to_return
total_payment = 0
percentage = (selected_client / 100.to_f) + 1.to_f

while time_passed > 0
  if total_payment == 0
    total_payment = loan * percentage
  else
    total_payment = total_payment * percentage
  end
  time_passed = time_passed - 1
end

puts "You have to pay a total of $#{total_payment.round(2)} to the bank."