Excel Sheet Column Number

Problem: Excel Sheet Column Number

This problem is as easy as Excel Sheet Column Title. Just consider a letter as a number from 1 to 26 and do the rest.

Code in Python:

class Solution(object):
    def titleToNumber(self, s):
        """
        :type s: str
        :rtype: int
        """
        letters = " " + string.uppercase
        ans = 0
        for c in s:
            ans = ans * 26 + letters.index(c)
        return ans