so s3 is the final state that we have after encoding these three symbols and then what ans lets us do is decode from that state and when we decode from that state and s will tell us the last symbol that was encoded and then tell us the the previous state that came before that so so that's why it's it's like a stack because if you ask me an s what was the lesson well that was encoded it's gonna be beat or it's gonna be the this beat not the first one hopefully this will be more clear as I've got some more examples