CBSE Class 12 Computer Science is a difficult subject to manage because it has an equal portion of both theory and practical. You need to first complete your theory portion and then move on to the coding. By going through the repeated questions, you can learn about the most commonly asked coding questions, along with some important theory topics. To understand the marks allotted for the different topics, you need to download the CBSE Class 12 Computer Science Exam Pattern 2026. After you are done with your syllabus, you can improve your understanding of the subject using the CBSE Class 12 Computer Science Sample Paper 2026 . After completing the sample question papers, you can carry forward with the CBSE Class 12 Computer Science Previous Year Question Paper . Below, we have compiled some important CBSE Class 12 Computer Science Exam 2026 Repeated Questions for your reference.

CBSE Class 12 Computer Science Exam 2026 Repeated Questions

The theory paper in Computer Science will be conducted for 70 marks. Some topics will hold more weightage as compared to the other topics. You can check out the important questions from those topics below:

Question 1. Atharva is a Python programmer working on a program to find and return the maximum value from the list. The code written below has syntactical errors. Rewrite the correct code and underline the corrections made.

def max_num (L) :

max=L (0)

for a in L :

if a > max

max=a

return max

Question 2. Differentiate between wired and wireless transmission, or differentiate between URL and domain name with the help of an appropriate example.

Question 3. (a) Given is a Python list declaration :

Listofnames= [ "Aman " , "Ankit " , "Ashish" , "Rajan" , "Rajat " ]

Write the output of :

print (Listofnames [—1:-4:-1])

(b) Consider the following tuple declaration :

tupl= (10, 20, 30, (10,20,30), 40)

Write the output of :

print (tupl . index (20) )

Question 4. Explain the concept of an alternate key in the relational database management system with an appropriate example.

Question 5. Write the output of the code given below

def short_sub (lst,n):

for i in range (0,n):

if len (lst[i]) >4:

lst [i] =lst [i]+lst [i]

else:

lst [i]=lst [i]

subject=['CS', 'HINDI', 'PHYSICS', 'CHEMISTRY', 'MATHS']

short_sub (subject, 5)

print (subject)

Question 6. Write the output of the code given below

a=30

def call (x):

global a

if a%2==0:

x+=a

else:

x-=a

return x

x=20

print (call (35), end="#")

print (call (40),end= "@")

Question 7. (a) Consider the following tables — LOAN and BORROWER

Table: LOAN

Table: BORROWER

How many rows and columns will there be in the natural join of these two tables?

(b) Write the output of the queries (i) to (iv) based on the table, WORKER given below:

(i) SELECT F NAME, CITY FROM WORKER ORDER BY STATE DESC;

(ii) SELECT DISTINCT (CITY) FROM WORKER;

(iii) SELECT F_NAME, STATE FROM WORKER WHERE L_NAME LIKE '_HA%'

(iv) SELECT CITY, COUNT(*) FROM WORKER GROUP BY CITY;

Also Read CBSE Class 12 Computer Science Weightage 2026

Question 8. A list contains the following records of customers: [Customer_name, Room Type]. Write the following user-defined functions to perform the given operations on the stack named 'Hotel':

(i) To push customers' names of customers who are staying in the 'Deluxe' Room Type.

(ii) To pop the names of customers from the stack and display them. Also, display "Underflow" when there are no customers in the stack.

For example: If the lists with customer details are as follows:

["Siddarth", "Delux"]

["Rahul", "Standard"]

["Jerry", "Delux"]

The stack should contain:

Jerry

Siddharth

The output should be:

Jerry

Siddharth

Underflow

Which of the following options correctly implements the described functionality for the stack named 'Hotel'?

a) PushDeluxCustomers() and PopCustomers()

b) PushCustomers() and PopDeluxCustomers()

c) PushDeluxCustomers() and PopDeluxCustomers()

d) PushCustomers() and PopCustomers()

Question 9. Write a function count Dwords ( ) in Python to count the words ending with a digit in a text file " Details . txt”.

Example:

If the file content is as follows:

On seat2 VIP 1 will sit and

On seat1 VVIP2 will be sitting

Output will be:

Number of words ending with a digit is 4

Question 10. (a) Write one difference between CSV and text files.

(b) Write a program in Python that defines and calls the following user-defined functions:

1. COURIER_ ADD(): It takes the values from the user and adds the details to a CSV file 'courier.csv'. Each record consists of a list with field elements as a cid, s_name, Source, and destination to store Courier ID, Sender name, Source, and destination address, respectively.

2. COURIER_SEARCH (): Takes the destination as the input and displays all the courier records going to that destination.

Understanding different topics and working through the CBSE Class 12 Computer Science Syllabus 2026 efficiently is the first step towards getting good marks in Computer Science. If you solve the CBSE Class 12 Computer Science Exam 2026 Repeated Questions regularly, you can ace your preparation. Do not forget to also work on MCQs and coding, especially to understand the topics easily.