# Roman numerals are represented by seven different symbols:
# I, V, X, L, C, D and M.
#
# Symbol       Value
# I             1
# V             5
# X             10
# L             50
# C             100
# D             500
# M             1000
#
# For example, 2 is written as II in Roman numeral, just two ones added
# together. 12 is written as XII, which is simply X + II. The number 27 is
# written as XXVII, which is XX + V + II.
#
# Roman numerals are usually written largest to smallest from left to right.
# However, the numeral for four is not IIII. Instead, the number four is
# written as IV. Because the one is before the five we subtract it making four.
# The same principle applies to the number nine, which is written as IX. There
# are six instances where subtraction is used:
#
#     I can be placed before V (5) and X (10) to make 4 and 9.
#     X can be placed before L (50) and C (100) to make 40 and 90.
#     C can be placed before D (500) and M (1000) to make 400 and 900.
#
# Given a roman numeral, convert it to an integer.

#
def romanToInt(s: str) -> int:
    resultado: int = 0
    for index in range(len(s)):
        match s[index]:
            case "I":
                if (index < (len(s) - 1)) and (
                    s[index + 1] == "V" or s[index + 1] == "X"
                ):
                    continue
                resultado += 1
            case "V":
                if s[index - 1] == "I" and index > 0:
                    resultado += 4
                    continue
                else:
                    resultado += 5
            case "X":
                if (index < (len(s) - 1)) and (
                    s[index + 1] == "L" or s[index + 1] == "C"
                ):
                    continue
                if s[index - 1] == "I" and index > 0:
                    resultado += 9
                    continue
                else:
                    resultado += 10
            case "L":
                if s[index - 1] == "X" and index > 0:
                    resultado += 40
                    continue
                else:
                    resultado += 50
            case "C":
                if (index < (len(s) - 1)) and (
                    s[index + 1] == "D" or s[index + 1] == "M"
                ):
                    continue
                if s[index - 1] == "X" and index > 0:
                    resultado += 90
                    continue
                else:
                    resultado += 100
            case "D":
                if s[index - 1] == "C" and index > 0:
                    resultado += 400
                    continue
                else:
                    resultado += 500
            case "M":
                if s[index - 1] == "C" and index > 0:
                    resultado += 900
                    continue
                else:
                    resultado += 1000
    return resultado