I used getc and the idea of finite automaton to solve this problem and my program is working fine on the sample test case as well as all test cases given in thread.
Still I am getting WA#1. I know it is not same as sample case.
Please give me some good test from case 1.
Thanks.

I have used getc(stdin), but if I give input from file by <<, I have to put an extra getc(stdin), whereas if I write it on command prompt, that is not required. Why is this so? Why input from file has an extra character at end of line?

I thought that in the end of n-th line it is EOF. But this line finishes by '\n' similarly as another lines. That's why I got WA#1.