Problems with a Pizza menu

class Pizza
  def initialize()
  end #def initialize
  def list()
    print <<EOF
     1)  Southwestern Large 17.95                  17) House Mized Green Large 3.50
     2)  Southwestern Small 10.95                  18) House Mixed Green Small 1.95
     3)  Pizza Margherite Large 10.95              19) Mozzarella Caprese 7.95
     4)  Pizza Margherite Small 8.95
     5)  Pepperoni Classico Large 17.95            Starters
     6)  Pepperoni Classico Small 10.95            20) Antipasto Platter 7.95
     7)  Hawaiian Pizza Large 17.95                21) Cheese Bread 5.95
     8)  Hawaiian Pizza Small 10.95                22) Breadsticks and Dip 2.50
     9)  Greek Pizza Large 17.95
     10) Greek Pizza Small 10.95                   Pasta
     11) Pesto Eggplant Large 17.95                23) Fusilli Lunghi 13.25
     12) Pesto Eggplant Small 10.95                24) Fettuccine Alfredo 14.75
     13) Wild Mushrooms and Artichokes Large 17.95 25) Lasagna Fresco 12.75
     14) Wild Mushrooms and Artichokes Small 10.95
     Drinks                                        Desert
     15) Sodas with Refils 1.75                    26) Soumoni 2.95
     16) Cofee and Tea 1.25                        27) Chocolate Lava Cake 5.00
     28) Finished Ordering 
EOF
  end
  def vote
  @total=0
  list
  STDOUT.print "choose"
  STDOUT.flush
    while guess = STDIN.gets
    list
    STDOUT.print "choose"
    STDOUT.flush
    guess.chop!
    STDOUT.print "> #{guess} <\n"
    if guess == 28.to_s
    exit()
    end #if
    @total+=case guess.to_i
    
    when 16
    1.25
    when 15
    1.75
    when 18
    1.95
    when 22
    2.50
    when 26
    2.95
    when 17
    3.50
    when 27
    5.00
    when 21
    5.95
    when 19,20
    7.95
    when 4
    8.95
    when 2,3,6,8,10,12,14
    10.95
    when 25
    12.75
    when 23
    13.95
    when 24
    14.75
    when 1,5,7,11,13
    17.95
   
    else
    arrPrice[2]
    end
    STDOUT.print "TOTAL : #{@total}\n"
    STDOUT.flush
    end #while
  
  
  
  
  end #def vote
  
end #class Pizza 

t=Pizza.new
t.vote

prices = 
{
   # item number => price
   1 => 12.78,
   2 => 14.62,
   3 => 100.42
}

# Now you can do something like

selection = gets.chomp.to_i
print "Price: "
puts prices[selection]