LeetCode 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 
    ...

Example 1:

Input: 1
Output: "A"

Example 2:

Input: 28
Output: "AB"

Example 3:

Input: 701
Output: "ZY"

 

此题卡顿半天，上网参考代码，但看许多人解释这是二十六进制转化，思忖再三觉得不是。

另此处头插字符串很有创意。

 

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