171. Excel Sheet Column Number

https://leetcode.com/problems/excel-sheet-column-number/

Python

class Solution:
    def titleToNumber(self, columnTitle: str) -> int:
        result = 0
        power = 0
        for char in columnTitle[::-1]:
            result += (ord(char)-64) * (26 ** power)
            power += 1
        return result

Go

func titleToNumber(columnTitle string) int {
    length := len(columnTitle)
    var result float64 = 0
    var power int = 0

    for i := range(columnTitle) {
        result += float64(columnTitle[length-i-1] - 64) * math.Pow(float64(26), float64(power))
        power += 1
    }
    return int(result)
}