168. Excel Sheet Column Title

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 

class Solution {public:    string convertToTitle(int n) {        string result;        while(n>0){            char c=65+(n-1)%26;            n=(n-1)/26;            result=c+result;        }               return result;    }};

基本思想:其实是求解一个十进制数如何转换成一个二十六进制数