Objective: Design a three 4-bit numbers adder.
Details of the design: Ripple Carry Adder (RCA) performs addition of two 𝑛-bit numbers. Therefore, the adder shown in the figure below performs the addition in two stages as follows:
1- In the first stage, we need to reduce the problem of adding three numbers into adding two 𝑛-bit numbers. The 8-bits of S and C will be computed at the same time.
2- In the second stage, RCA is used to compute the summation and the carry.
Note: your design must be built up using the minimum number of Half Adders (HA).
Test Bench: For simplicity, the Test bench can be conducted using three different tuples only (eg. T1=(X= 1100, Y= 1101, Z=1110), T2=(X= 1111, Y= 1000, Z= 1001), T3=(X= 1110, Y= 0101, Z= 0111)
