class Solution:
    def __init__(self):
        self.val = {
            'A': 1, 'B': 2, 'C': 3, 'D': 4,
            'E': 5, 'F': 6, 'G': 7, 'H': 8,
            'I': 9, 'J': 10, 'K': 11, 'L': 12,
            'M': 13, 'N': 14, 'O': 15, 'P': 16,
            'Q': 17, 'R': 18, 'S': 19, 'T': 20,
            'U': 21, 'V': 22, 'W': 23, 'X': 24,
            'Y': 25, 'Z': 26
        }

    def titleToNumber(self, s: str) -> int:
        result = 0
        for exponent, letter in enumerate(reversed(list(s))):
            result += self.val[letter] * 26 ** exponent

        return result


print(Solution().titleToNumber("ZY"))