Leetcode: Excel Sheet Column Title

问题：

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

解答：

将十进制转为26进制

class Solution {
public:
    string convertToTitle(int n)
    {
        if (n < 1)
        {
            return "";
        } 
        else
        {
            string result = "";
            while (n)
            {
                n--;
                char ch = n % 26 + 'A';
                result += ch;
                n /= 26;
            }
            reverse(result.begin(), result.end());
            return result;
        }
    }
};

从右到左得到各位的字符，然后进行转置！