Hell yeah !!! A day long 1B- Spreadsheet

1B-spreadsheet

Ref : http://codeforces.com/problemset/problem/1/B

First, I didnt get AC jz coz  of some mysterious unknow off-by one error i can say...!

Here's my unaccepted code : 

while(C > 0){

                int x = 0;

                x = (C-1)%26;

                if(x == 0){

                 ans[i++] = 'Z';

                }

                else{

                    ans[i++] = 'A'+x-1;

                }

                C = (C-1)/26;

            }

Actually, I found that my logic is wrong :/

But when  I changed it to this, It got accepted : 

 while((C-1)/26){

                ans[i++] = (C-1)%26+'A';

                C = (C-1)/26;

            }

            ans[i++] = (C-1)%26+'A';