LeetCode 168. Excel Sheet Column Title

题目

class Solution {  public:      string convertToTitle(int n) {              string ans="";              while(n)          {             int x = (n-1) % 26;               ans += ('A'+ x );                n = (n-1) / 26;          }            string res="";            for(int i=ans.length()-1;i>=0;i--)          {              res += ans[i];          }            return res;        }  };