问题描述

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 

代码

class Solution {
public:
    string convertToTitle(int n) {
        string s="";
        while(n) {
        	s = (char)((n-1)%26+'A')+s;
        	n = (n-1)/26;
        }
        return s;
    }
};