Finite state machines: counter
q1 q0 x q1+ q0+ z1 z0  
0 0 0 0 0 0 0  
0 0 1 0 1 0 0
0 1 0 0 1 0 1
0 1 1 1 0 0 1
1 0 0 1 0 1 0
1 0 1 1 1 1 0
1 1 0 1 1 1 1
1 1 1 0 0 1 1
1c. Output: same as current state label
Note that the figure reverses our usual definition of the output bits