From: Hung Dao <mephis1987@...>
Date: 2006-12-10T23:15:15+09:00
Subject: Re: Need help on a program

#!/usr/bin/env ruby
@data = [
[
"M" , 1000],
["CM" , 900],
["D" , 500],
"CD" , 400],
[
["C" , 100],
[
"XC" , 90],
"L" , 50],
[
"XL" , 40],
[
["X" , 10],
["IX" , 9],
"V" , 5],
[
[
"IV" , 4],
"I" , 1]
[
]
@roman = %r{^[CDILMVX]*$}
@arabic = %r{^[0-9]*$}
def to_roman(num)
""
reply =
for key, value in @data
count, num = num.divmod(value)
reply << (key * count)
end
reply
end
def
to_arabic(rom)
reply = 0
for key, value in @data
while rom.index(key) == 0
reply += value
rom.slice!(key)
end
end
reply
end
$stdin.each do |line|
case line
when @roman
puts to_arabic(line)
when @arabic
puts to_roman(line.to_i)
end
end

----
Another solution from the pragmatic book : best quiz