Consider the following pseudo-code segment.

1.  input y {y is a three-digit hexadecimal number}

2.  d ← 0

3. for i = 1 to 3
     3.1. char ← i^th character from y reading from right to left

     3.2. if char = 'A or B or C or D or E or F'

       3.2.1. Convert char to its decimal equivalent

3.3. end if

3.4. d <- d + 16^i-1
4. end for

5. output d
 
(a) Trace the pseudo-code for the input y = A2E

(b) Briefly explain in words what this pseudo-code does, including its purpose. You only need to write two or three short sentences to answer this question.