For the given circuit $($Figure A$)$ and input, Write your answer without spaces as follows: $10101010.$

EN a b c $d_0{d}_1{d}_2{d}_3{d}_4{d}_5{d}_6{d}_7$

$1000$ The output is $\frac{?}{\text{b}\text{a}\text{r}}($ Blank $2)$