168. Excel Sheet Column Title（LeetCode）

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 
我想复杂了，下面是我的代码

 1 class Solution {
 2 public:
 3     string convertToTitle(int n) {
 4         map<int, string> m;
 5         vector<string> vet(1, "");
 6         string str = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
 7         for (int i = 1; i <= 26; i++)
 8         {
 9             string s = "";
10             s = str[i - 1];
11             vet.push_back(s);
12 
13         }
14 
15         for (int i = 0; i <= 26; i++)
16         {
17             m.insert(pair<int, string>(i, vet[i]));
18         }
19             cout<<m[26]<<endl;
20         stack<int> sta;
21         string str1 = "";
22         while (n)
23         {
24             if(n<=26)
25             {
26                 sta.push(n);
27                 break;
28             }
29             if(n%26==0)
30             {
31                 sta.push(26);
32                 n=n/26-1;
33             }
34             else
35              {sta.push(n%26);
36              n=n/26;
37              }
38         }
39         while(sta.size())
40         {
41             str1+=m[sta.top()];
42             sta.pop();
43         }
44         return str1;
45     }
46 };

我看别人提交的代码：

 1 class Solution {
 2 public:
 3         string convertToTitle(int n) {
 4                 string ret("");
 5                 if (n <= 0)
 6                     return ret;
 7 
 8                 while (n) {
 9                     --n;
10                     ret += string(1, ((n) % 26) + 'A');
11                     n /= 26;
12                 }
13                 reverse(ret.begin(), ret.end());
14                 return ret;
15             }
16         };