leetcode#168. Excel Sheet Column Title

Description

Given a positive integer, return its corresponding column title as appear in an Excel sheet.

For example:

1 -> A
2 -> B
3 -> C
...
26 -> Z
27 -> AA
28 -> AB 

Code

class Solution:
    def convertToTitle(self, n):
        """
        :type n: int
        :rtype: str
        """
        if n == 0:
            return ""
        else:
            return self.convertToTitle(int((n - 1) / 26)) + chr((n - 1) % 26 + ord('A'))

Conclusion

变型的进制问题。这里遇到个python3的坑，整数相除，得到的是浮点数了，不再取整了。