| Program | ROMAN.C ROMAN.CPP ROMAN.PAS |
Input and Output Write a program that accepts Roman numerals (one per line) and converts them to decimal form.
Remember, I=1, V=5, X=10, L=50, C=100, D=500, and M=1000. Furthermore, there are the following digraphs: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900. There may be at most three consecutive I, X, C or M. Thus the greatest possible number is 3999.
The program should reject improperly formed numerals.
Sample Input
MCMXCVIII
CCM
Sample Output
1998
This is not a valid number