Science (English Medium) कक्षा १२ - CBSE Important Questions for Computer Science (Python)

Write the output of the code given below:

def short_sub (1st, n):
for i in range (0, n):
      if len (1st) > 4:
          lst [i] = lst [i] + lst [i]
      else:
          lst [i] = lst [i]
subject = ['CS', 'HINDI', 'PHYSICS', 'CHEMISTRY', 'MATHS'] 
short_sub (subject, 5)
print (subject)

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="@")

Given is a Python list declaration:

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

Write the output of:

print (Listofnames [−1:−4:−1])

Consider the following tuple declaration:

tup1 = ( 10, 20, 30, (10, 20, 30), 40)

Write the output of:

print(tupl.index(20))

Which of the following is a valid keyword in Python?

Consider the given expression:

5<10 and 12>7 or not 7>4

Which of the following will be the correct output if the given expression is evaluated?

What possible output(s) are expected to be displayed on the screen at the time of execution of the following program:

import random
M=[5, 10, 15, 20, 25, 30]
for i in range(1, 3):
first=random.randint(2, 5)-1
sec=random.randint(3, 6)-2
third=random.randint(1, 4)
print(M[first],M[sec],M[third],sep="#") 

Predict the output of the code given below: 

def makenew(mystr):
     newstr.=.""
     count=0
     for i in mystr:
        if count%2 ! = 0:
           newstr=newstr+str(count)
        else:
           if i.lower():
      newstr = newstr + i.upper ()
           else:
               newstr = newstr + i
       count+=1
    Print(newstr)
makenew("No@1") 

Which of the following operators will return either True or False?

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

1. Add_Book(): Takes the details of the books and adds them to a CSV file ‘Book. csv'. Each record consists of a list with field elements such as book_ID, B_name and pub to store book ID, book name and publisher, respectively.
2. Search_Book(): Takes publisher name as input and counts and displays the number of books published by them. 

Shreyas is a programmer, who has recently been given a task to write a user-defined function named write_bin () to create a binary file called Cust_file.dat containing customer information – customer number (c_no), name (c_name), quantity (qty), price (price) and amount (amt) of each customer. 

The function accepts customer number, name, quantity and price. Thereafter, it displays the message 'Quantity less than 10.....Cannot SAVE', if the quantity entered is less than 10. Otherwise, the function calculates the amount as price*quantity and then writes the record in the form of a list into the binary file. 

import pickle
def write_bin ():
bin_file = ____________ # Statement 1
while True:
c_no = int (input (“enter customer name”))
c_name = input (“enter customer name”)
qty = int (input ("enter qty"))
price = int (input ("enter price”))
if ________ # Statement2
print (“Quantity less than 10.. Cannot SAVE")
else:
amt = price * gty
c_detail = [c_no, c_name, qty, price, amt]
__________ # Statement 3
ans = input (" Do you wish to enter more records y/n”) if ans. lower () == 'n’:
          __________ # Statement 4
    ____________ # Statement 5
____________#Statement 6

(i) Write the correct statement to open a file 'Cust_file.dat’ for writing the data of the customer.

(ii) Which statement should Shreyas fill in statement 2 to check whether the quantity is less than 10?

(iii) Which statement should Shreyas fill in Statement 3 to write data to the binary file and in Statement 4 to stop further processing if the user does not wish to enter more records?
                                      OR
(iii) What should Shreyas fill in Statement 5 to close the binary file named Cust_file.dat and in Statement 6 to call a function to write data in the binary file?

“In a Python program, if a break statement is given in a nested loop, it terminates the execution of all loops in one go.”

What possible outputs(s) will be obtained when the following code is executed?

import random
myNumber=random.randint (0, 3)
COLOR=["YELLOW", "WHITE", "BLACK", "RED"]
for I in range (1, myNumber) :
              print (COLOR [I], end="*")
       print ()

Consider the code given below:

b=100
def test(a):
   ______________ # missing statement
   b=b+a
   print (a,b)
test (10)
print (b)

Which of the following statements should be given in the blank for #Missing Statement, if the output produced is 110?

An exception may be raised even if the program is syntactically correct.

• Assertion(A): Python standard library consists of number of modules.
• Reasoning(R): A function in a module is used to simplify the code and avoids repetition.

The code given below accepts a number as an argument and returns the reverse number. Observe the following code carefully and rewrite it after removing all syntax and logical errors. Underline all the corrections made.

define revNumber (num) :
      rev = 0
      rem = 0
      While num > 0:
            rem ==num %10
            rev = rev*10 + rem
            num = num//10
            return rev
print (revNumber (1234))

Write a function countNow (PLACES) in Python, that takes the dictionary, PLACES as an argument and displays the names (in uppercase) of the places whose names are longer than 5 characters.
For example, Consider the following dictionary

PLACES={1:"Delhi",2:"London",3:"Paris",4:"New York",5:"Doha"}

The output should be:

• LONDON
• NEW YORK

Write the Python statement for the following task using the BUILT-IN function/method only:

To insert an element 200 at the third position, in the list L1.

Write the Python statement for the following task using the BUILT-IN function/method only:

To check whether a string named, message ends with a full stop/period or not.