Figure $3$ shows a design for three$-$input addition

$($i$.$e$.r=a+b+c)$ based on the $2-$input adders.

All values in the design are n$-$bit integers.

How would you modify the design to speed up the

array addition $R=A+B+C?R,A,B$ and $C$ are integer

arrays.

Analyse the speedup your design can achieve.

Figure $3$