Plus One

 1 vector<int> plusOne(vector<int>& digits) {
 2        
 3         vector<int>result(digits);
 4         bool flag = true;
 5         
 6         int index = result.size()-1;
 7         while ( index >= 0 )
 8         {
 9             result[index] = (result[index]+1)%10;
10             flag = (result[index--]==0)?true:false;
11             
12             if (!flag)
13                 return result;
14         }
15         
16         if (flag)
17         {
18             result.insert(result.begin(),1);
19         }
20         return result;
21     }