Write a program that converts Roman numerals to their decimal value. Your program should
recognize the Roman numerals I, V, X, L, C, D, and M, which have the decimal values of 1, 5, 10, 50, 100, 500,
and 1000 respectively.
Most importantly, your program must understand the subtractive forms such as IX (9) or CM (900).
Your program may be designed to run from a command line, or as part of a web page if you choose.
Some sample values:
XLIII = 43
MXXIX = 1029
MCMDXIV = 2414