Roman Numerals to Number Converter

To convert a Roman numeral to its corresponding number, you can use the following algorithm:

Create a dictionary that maps each Roman numeral symbol to its corresponding value.

Initialize the result variable to 0.

Iterate over the Roman numeral from left to right.

If the current symbol is smaller than the next symbol, subtract its value from the result. Otherwise, add its value to the result.

Repeat step 3-4 until the end of the Roman numeral is reached.

Return the result.

Here is the Python code for a function that implements this algorithm:


def convert_to_number(roman_num):

roman_dict = {'M': 1000, 'D': 500, 'C': 100, 'L': 50, 'X': 10, 'V': 5, 'I': 1}

result = 0

for i in range(len(roman_num)):

if i < len(roman_num) - 1 and roman_dict[roman_num[i]] < roman_dict[roman_num[i+1]]:

result -= roman_dict[roman_num[i]]


result += roman_dict[roman_num[i]]

return result

Here are a few examples of how to use the function:


>>> convert_to_number('IX')


>>> convert_to_number('XXVII')


>>> convert_to_number('LXXXIX')


>>> convert_to_number('MCMLXXII')


>>> convert_to_number('MMXXII')


Note that this function only works for valid Roman numerals, and does not check for errors such as invalid characters or invalid sequences of characters.

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