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 

十进制转26进制的问题。注意每次有n-1是因为‘A’=1

class Solution {        public String convertToTitle(int n) {        String res="";        while(n!=0){            char temp = (char)('A'+(n-1)%26);            res = temp+res;            n = (n-1)/26;        }        return res;    }}