Excel Sheet Column Title

solution.py

# https://leetcode.com/problems/excel-sheet-column-title
class Solution:
    def convertToTitle(self, columnNumber: int) -> str:
        """
        Success
        Details 
        Runtime: 28 ms, faster than 77.90% of Python3 online submissions for Excel Sheet Column Title.
        Memory Usage: 14.1 MB, less than 70.63% of Python3 online submissions for Excel Sheet Column Title.
        """
        if columnNumber <= 26:
            return chr(64+columnNumber)
        
        left = columnNumber // 26
        right = columnNumber % 26
        
        if (right == 0):
            left = (left -1) if left > 1 else 1
            return self.convertToTitle(left) + self.convertToTitle(26)
        
        return self.convertToTitle(left) + self.convertToTitle(right)

(26^0*x)+(26^1*1)+(26^2*1)+(26^3*1) = AAAA (where x = 1)
'ZZ' = 702 = ((26^0*26) + (26^1*26)) = 26 + 676 
'AB' = 26^1*1 + 2 = 28
'BY' = 26*1*2 + 25 = 77