Excel Sheet Column Number LeetCode solution in Python

1
def let_to_num(char):
2
    abc = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
3
    return abc.index(char) + 1
4

5

6
class Solution:
7
    def titleToNumber(self, columnTitle: str) -> int:
8
        ans = 0
9
        for i in range(len(columnTitle)):
10
            ans *= 26
11
            ans += let_to_num(columnTitle[i])
12
        return ans