(a) Write the output of the following code :

``python

def Exam2026(given) :

new=[]

for ch in given[1:-1]:

if ch.isupper():

new.reverse()

elif ch not in new:

new.append(ch)

elif ch in new:

new.pop()

print(new)

Exam2026("Gold-24Medals")

`

OR

(b) Write the output of the following code :

`python

def Exam2026(given):

new = 0

while given:

if new % 2:

new += given % 10

else:

new += given % 5

print(new, end='-')

given //= 10

Exam2026(123456)

``

Both snippets must be traced character-by-character / digit-by-digit — no shortcuts work here.

Part (a) — list as a toggle stack

• given[1:-1] strips the first and last character of "Gold-24Medals", leaving the 11 characters o,l,d,-,2,4,M,e,d,a,l.
• Every lowercase/non-letter character is appended if new, but if it is already present the list is popped (undo); an uppercase letter reverses the whole list instead of being stored.
• Tracing in order gives new = ['4','2','-','d','l','o'] after 'M' reverses ['o','l','d','-','2','4'], then 'e' is added and removed by 'd', and 'a' is added and removed by 'l'.

Part (b) — alternating mod-5/mod-10 accumulator

• new starts even (0), so the first digit is added using %5; whenever new becomes odd, the next digit is added using %10 instead, alternating the rule every step as given is stripped one digit at a time from the right using //=10.

Exam trap

• Forgetting that new%2 is checked BEFORE updating new each iteration, and mixing up isupper() with isalpha(), are the most common tracing errors.