Thank you for your help. Actually, the input file is formatted to have only 60 characters in each line and then it moves to the new line. So, that's the input file format when you see just a single S on the last line of the second entry.
On a different note, for the first entry, the sequence length value you get in your output (110) is one less than the actual sequence length which is 111. However, my output gives me a sequence length of 115, which is even worse. Do you know where the error might be?