I'm currently reading Feynman Lectures on Computation and got stuck in problem 3.1 which says
Suppose we feed a sequence of 1's and 0's - a binary number - into a machine. Design a machine which performs a pairwise sum of the digits, that is, one which takes the incoming digits two at a time and adds them, spitting the result out in two steps. So, if two digits come in as 00, it spits out 00; a 10 or 01 results in a 01 (1+0 = 10+11!); but a 11 results in binary 10: 1+1 = 2, in decimal, 10 in binary. I will give you a hint: the machine will require four states.
I don't ask you the answer. Just I don't understand what this is asking.
For example, when the input sequences are
(00)(01)(10)(11)(10)(00), output sequences should be what?
Thanks in advance.