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
Analyse：十进制转换为二十六进制，用A~Z来表示。
1 class Solution { 2 public: 3 string convertToTitle(int n) { 4 string result; 5 while(n){ 6 result += (--n) % 26 + ‘A‘; 7 n /= 26; 8 } 9 reverse(result.begin(), result.end()); 10 return result; 11 } 12 };
原文：http://www.cnblogs.com/amazingzoe/p/4415657.html