So I was reading Micheal Sipser's Introduction to TOC and when I stumbled upon this aforementioned question , he'd the following dfa :
Now, I came up with a much better DFA with only 4 states :
I read in another thread that the minimum number of states for a DFA for this language is 8. But , I came up with 4.
Where am I going wrong ? (I tried testing this DFA with a plethora of input strings , seems ok to me)