# Euler Solution 89

### From ProgSoc Wiki

# Solutions to Problem 89

Calculate the number of characters saved by reducing a list of roman numerals to their shortest variants following certain rules. (eg XVIIII = XIX)

## Python by Althalus

Runtime: 1ms

I did write functions to convert roman numerals to numbers, and numbers to roman numerals, but realised there was a better way before I got it working right. The information given in the problem is enough to identify exactly what we can change to minimise these numerals.

file = open('roman.txt') numerals = file.read() count = len(numerals) numerals = numerals.replace('VIIII', 'IX') numerals = numerals.replace('IIII', 'IV') numerals = numerals.replace('LXXXX', 'XC') numerals = numerals.replace('XXXX', 'XL') numerals = numerals.replace('DCCCC', 'CM') numerals = numerals.replace('CCCC', 'CD') count -= len(numerals) print count