Validating Roman Numerals Hackerrank Solution Python

You are given a string, and you have to validate whether it’s a valid Roman numeral. If it is valid, print True. Otherwise, print False. Try to create a regular expression for a valid Roman numeral.

Input Format

A single line of input containing a string of Roman characters.

Output Format

Output a single line containing True or False according to the instructions above.

Constraints

The number will be between 1 and  3999(both included).

Sample Input

CDXXI

Sample Output

True

References

Regular expressions are a key concept in any programming language. A quick explanation with Python examples is available here. You could also go through the link below to read more about regular expressions in Python.

Code:

#Validating Roman Numerals

import re
regex_pattern = r"M{0,3}(C[MD]|D?C{0,3})(X[CL]|L?X{0,3})(I[VX]|V?I{0,3})$"	# Do not delete 'r'.
print(str(bool(re.match(regex_pattern, raw_input()))))


#Validating Roman Numerals