In each of the systems that we have considered so far, we have not worried about initializing the system. They all produce the correct output, once the first 0 input is received. If we are willing to ignore the output prior to that, we do not need to be concerned with initialization. If we need to know the output from the first input, then we must initialize the system to state A (or 000 in the first example). The next two examples do depend upon initializing the system to state A, that is, we need to know where the starting point is.