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 ← ith 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 + 16i-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.