Search:

If you don't know the rules for constructing Roman numerals it will be very hard to write code to convert them. Do some research.

Given "IX" what does the code need to do when it sees the 'I'?

Does the code need to reject invalid input: IXL or MCCM

Can you explain the logic for what to do with each Roman numeral character as it is read from the full number?
For example what would you do with the 'C' from CM?

Can you post some examples of the input and desired output?