first_name = gets.chomp

first_name.capitalize!

first_name.upcase!

first_name.downcase!

print <<EOF
  # 多行输出
EOF

# 我是注释

#{first_name}

if a < b
  puts '1'
elsif b < a
  puts '2'
end    

class Classname
  def functionname(params)
    puts params
  end
end

class1 = Classname.new
class1.functionname('1')
unless
unless false
  print 'ok'
else
  print 'no'
end    

print 'puts'

user_input = gets.chomp

user_input.downcase!

if user_input.include?"s"
  print 'has s'
end

# s -> th
user_input.gsub!(/s/,"th")

puts 'okok #{user_input}'

counter = 1

while counter < 11
  puts counter
  counter = counter + 1
end

counter = 1
until counter > 10
  print counter
  counter = counter + 1
end 
 

for num in 1...10
  puts num
end  

i = 20
loop do
  i -= 1
  print "#{ i }"
  break if i <= 0
end  

i = 20
loop do
 i -= 1
 next if i%2 != 0
 print "#{i}"
 break if i <= 0
end

my_array = [1,2,3,4,5]

numbers = [1, 2, 3, 4, 5]

# one way to loop
numbers.each { |item| puts item }

# another way to loop
numbers.each do |item|
 puts item
end

10.times { print 'ok'})

num = 1

while num <= 50 do
  print num
  num += 1
end  

num = 1
until num > 50 do
  print num
  num += 1
end  

num = 0

loop do
  num += 1
  print "Ruby!"
  break if num == 30
end  

text.split(",")

puts "Text to search through: "
text = gets.chomp
puts "Word to redact"
redact = gets.chomp

words = text.split(" ")

words.each do |word|
  print word
end