Computer Science Class XII (2016-17)
SQP – Computer Science (Code: 083)
Class XII (2016-17)
Time: 3Hrs. MM: 70
i. All Questions are Compulsory.
ii. Programming Language : Section – A : C++
iii. Programming Language : Section – B : Python
iv. Answer either Section A or B and Section C is compulsory
Section – A
1 (a) Explain Conditional Operator with suitable example? 2
Conditional operator is also known as ternary operator because it requires three operands and can be used to replace simple if-else code. It is used to check the condition and execute first expression if condition is true else execute other.
Conditional expression? Expression 1 : Expression 2;
If the conditional expression is true then expression 1 executes otherwise expression 2 executes.
(b) Which C++ header file(s) are essentially required to be included to run/execute the following C++ code : 1
<iostream.h> for input output
<string.h> for strcat function
(c) Rewrite the following program after removing the syntactical errors (if any). Underline each correction.
Correction in the code:
(d) Write the output of the following C++ program code: Note: Assume all required header files are already being included in the program.
36 50 46 42
(e) Write the output of the following C++ program code: Note: Assume all required header files are already being included in the program.
Registration@5000 Registration with Discount@4000 ICT@7000 Cyber Crime@6500 Genetic Mutation@7000 Cyber Crime@6500
(f) Observe the following program carefully and attempt the given questions:
I. Out of all the four courses stored in the variable courses, which course will never be displayed in the output and which course will always be displayed at first in the output?
As loop is beginning from 1 and not 0, M.Tech will never be displayed in the output. MCA will always be displayed at first in the output as it is at index 1.
II. Mention the minimum and the maximum value assigned to the variable ch?
Minimum value of ch=1
Maximum value of ch=3
2(a) What do you understand by Function overloading or Functional polymorphism? Explain with suitable example.
It is a method of using the same function or method to work using different sets of input. Function overloading is one of the example of polymorphism, where more than one function carrying same name behave differently with different set of parameters passed to them.
(b) Answer the questions(i) and (ii) after going through the following class:
I. What is Function 1 referred as? When will it be executed?
I. Constructor. It will be executed at the time of object creation.
II. Write suitable C++ statement to invoke Function. 2
II. planet p;
p.display(“Pluto”, ”7.5 Billion Km”);
(c) Define a class DanceAcademy in C++ with following description:
Enrollno of type int
Name of type string
Style of type string
Fee of type float
A member function chkfee( ) to assign the value of fee variable according to the style entered by the user according to the criteria as given below:
Style Fee Classical 10000 Western 8000 Freestyle 11000
A function enrollment() to allow users to enter values for Enrollno, Name, Style and call function chkfee()to assign value of fee variable according to the Style entered by the user.
A function display() to allow users to view the details of all the data members.
(d) Answer the questions (i) to (iv) based on the following:
(i) Name the type of inheritance illustrated in the above C++ code.
(ii) Write the names of all the members, which are accessible from the objects belonging to class outdoor_sports.
Data Members: None
Member Functions: oEntry(), oShow()
(iii) Write the names of all the member functions, which are accessible from the member function of class sports.
registration(), showdata(), oEntry(), oShow(), get_ofee(), iEntry(), iShow(), get_ifee()
(iv) What will be the size of the object belonging to class indoor_sports?
3(a) Write the definition of a function grace_score (int score , int size) in C++, which should check all the elements of the array and give an increase of 5 to those scores which are less than 40. 3
Example: if an array of seven integers is as follows: 45, 35, 85, 80, 33, 27, 90
After executing the function, the array content should be changed as follows: 45, 40, 85, 80, 38, 32, 90
(b) An array P is stored along the column in the memory with each element requiring 2 bytes of storage. If the base address of the array P is 26500, find out the location of P. 3
Total number of rows= 30
Total size= 2 bytes
Base Address= 26500
LOC (P[I][J]) = BaseAddress+((I-LBR) + (J-LBC) * R)*W
Assuming Lower Bound of Row(LBR)=0
Lower Bound of Column(LBC)=0
Total number of Rows(R)=30
Size of each element(W)=2
LOC(P)= 26500 +((20-0)+(10-0)*30)*2
LOC(P)= 26500 +640
(c) Write the definition of a member function push() for a class Library in C++ to insert a book information in a dynamically allocated stack of books considering the following code is already written as a part of the program:
(d) Write a user-defined function swap_row(int ARR[ ], int R, int C) in C++ to swap the first row values with the last row values:
For example if the content of the array is:
10 20 30
40 50 60
70 80 90
Then after function call, the content of the array should be:
70 80 90
40 50 60
10 20 30
(e) Evaluate the following POSTFIX expression. Show the status of Stack after execution of each operation separately: 45, 45, +, 32, 20, 10, /, -, *
Element Scanned Stack Status 45 45 45 45, 45 + 90 32 90, 32 20 90, 32, 20 10 90, 32, 20, 10 / 90, 32, 2 - 90, 30 * 2700
Hence the final result is 2700
4(a) Find the output of the following C++ code considering that the binary file already exists on the hard disk with 2 records in it.
(b) Write a user defined function word_count() in C++ to count how many words are present in a text file named “opinion.txt”. For example, if the file opinion.txt contains following text: Co-education system is necessary for a balanced society. With co-education system, Girls and Boys may develop a feeling of mutual respect towards each other.
The function should display the following: Total number of words present in the text file are: 24
(c) Write a function display () in C++ to display all the students who have got a distinction(scored percentage more than or equal to 75) from a binary file “stud.dat”, assuming the binary file is containing the objects of the following class:
Section – B (Python)
1 (a) Carefully observe the following python code and answer the questions that follow:
On execution the above code produces the following output.
Explain the output with respect to the scope of the variables. 2
Names declared with global keyword have to be referred at the file level. This is because the global statement indicates that the particular variable lives in the global scope. If no global statement is being used, the variable with the local scope is accessed. Hence, in the above code the statement succeeding the statement
global x informs python to increment the global variable x Hence the output is 6 i.e 5+1 which is also the value for global x.
(b) Name the modules to which the following functions belong: 1
a. uniform() b. fabs()
(c) Rewrite the following code after removing the syntactical errors (if any). Underline each correction. 2
(d) Observe the following Python code carefully and obtain the output, which will appear on the screen after execution of it. 2
(e) What output will be generated when the following Python code is executed? 3
(f) Observe the following program and answer the questions that follow:
a. What is the minimum and maximum number of times the loop will execute?
Minimum Number = 1
Maximum Number = 3
b. Find out, which line of output(s) out of (i) to (iv) will not be expected from the program?
Line iv is not expected to be a part of the output
2a. Explain the two strategies employed by Python for memory allocation.
Python uses two strategies for memory allocation:
i. Reference counting
ii. Automatic garbage collection.
Reference Counting: works by counting the number of times an object is referenced by other objects in the system. When an object’s reference count reaches zero, Python collects it automatically.
Automatic Garbage Collection: Python schedules garbage collection based upon a threshold of object allocations and object deallocations. When the number of allocations minus the number of deallocations are greater than the threshold number, the garbage collector is run and the unused block of memory is reclaimed.
b. Observe the following class definition and answer the questions that follow:
i. Write statement to invoke Function 1.
ii. On Executing the above code, Statement 2 is giving an error explain.
The statement 2 is giving an error because __Systemdate is a private variable and hence cannot be printed outside the class.
c Define a class PRODUCT in Python with the following specifications.
Pid – A string to store product id.
Pname – A string to store the name of the product.
Pcostprice – A decimal to store the cost price of the product
Psellingprice – A decimal to store Selling Price
Margin – A decimal to be calculated as Psellingprice – Pcostprice
Remarks – To store ”Profit” if Margin is positive else “Loss” if Margin is negative.
A constructor function to initialize All the data members with valid default values.
A method SetRemarks() that assigns Margin as Psellingprice – Pcostprice and sets Remarks as mentioned below:
Margin Remarks <0 (negative) Loss >0 (positive) Profit
A method Getdetails() to accept values for Pid, Pname, Pcostprice, Psellingprice and invokes SetRemarks() method.
A method Setdetails() that displays all the data members.
d. Answer the questions (i) to (iv) based on the following: 4
i. Which type of Inheritance is demonstrated in the above code?
ii. Explain Statement 1 and 2.
Statement 1 and 2 invoke the getSdata() function of class Shop and getData() function of class Brand respectively.
iii. Name the methods that are overridden along with their class name.
getdata() method of class Brand is overridden. When object of class Mall is created,
M = Mall()
getdata() method of class Mall is invoked and not of class Brand is
iv. Fill Blank 1 with a statement to display variable category of class Brand.
3a. Consider the following unsorted list: 95 79 19 43 52 3
Write the passes of bubble sort for sorting the list in ascending order till the 3rd iteration. 3
[79, 19, 43, 52, 3, 95]
[19, 43, 52, 3, 79, 95]
[19, 43, 3, 52, 79, 95]
b. Kritika was asked to accept a list of even numbers but she did not put the relevant condition while accepting the list of numbers. You are required to write a code to convert all the odd numbers into even by multiplying them by 2. 3
c. Aastha wants to create a program that accepts a string and display the characters in the reverse order in the same line using a Stack. She has created the following code, help her by completing the definitions on the basis of requirements given below : 4
self.mystr= ________________ # Accept a string
self.mylist =________________ # Convert mystr to a # list
Write code to display while removing elements from the stack.
d. Write a generator function generates q() that displays the squareroots of numbers from 100 to n where n is passed as an argument. 2
e. Evaluate the following Postfix expression: 20, 10, -, 15, 3, /, +, 5, *
Symbol Operation Stack Result 20 Push 20 10 Push 20, 10 - Pop(10) Pop(20) Push(20-10) =10 15 Push 10, 15 3 Push 10, 15, 3 / Pop(3) Pop(15) Push(15/3) =5 10, 5 + Pop(5) Pop(10) Push(10+5)=15 15 5 Push 15, 5 * Pop(5) Pop(15) Push(15*5) =75 75 75
4a Observe the following code and answer the questions that follow:
File = open(“Mydata”, “a”)
i. What type (Text/Binary) of file is Mydata?
ii. Fill the Blank 1 with statement to write “ABC” in the file “Mydata”
b) A text file “Quotes.Txt” has the following data written in it:
Living a life you can be proud of
Doing your best
Spending your time with people and activities that are important to you
Standing up for things that are right even when it’s hard
Becoming the best version of you
Write a user defined function to display the total number of words present in the file.
c. Consider the following class declaration and answer the question that follows:
Anuj has been asked to display all the students who have scored less than 40 for Remedial Classes. Write a user defined function to display all those students who have scored less than 40 from the binary file “Student.dat” assuming it stores all the object of the class Student mentioned above. 3
Section – C
5 (a) Observe the table ‘Club’ given below:
Club Member_id Member_Name Address Age Fee M002 Nisha Gurgaon 19 3500 M003 Niharika New Delhi 21 2100 M004 Sachin Faridabad 18 3500
i. What is the cardinality and degree of the above given table?
ii. If a new column contact_no has been added and three more members have joined the club then how these changes will affect the degree and cardinality of the above given table.
(b) Write SQL commands for the queries (i) to (iv) and output for (v) to(viii) based on the tables ‘Watches’ and ‘Sale’ given below.
Watches Watchid Watch_Name Price Type Qty_Store W001 HighTime 10000 Unisex 100 W002 LifeTime 15000 Ladies 150 W003 Wave 20000 Gents 200 W004 HighFashion 7000 Unisex 250 W005 GoldenTime 25000 Gents 100
Sale Watchid Qty_Sold Quarter W001 10 1 W003 5 1 W002 20 2 W003 10 2 W001 15 3 W002 20 3 W005 10 3 W003 15 4
i. To display all the details of those watches whose name ends with ‘Time’
select * from watches where watch_name like ‘%Time’
ii. To display watch’s name and price of those watches which have price range in between 5000-15000.
select watch_name, price from watches where price between 5000 and 15000;
iii. To display total quantity in store of Unisex type watches.
select sum(qty_store) from watches where type like ’Unisex’;
iv. To display watch name and their quantity sold in first quarter.
select watch_name, qty_sold from watches w, sale s where w.watchid=s.watchid and quarter=1;
v. select max(price), min(qty_store) from watches;
max(price) min(qty_store) 25000 100
vi. select quarter, sum(qty_sold) from sale group by quarter;
quarter sum(qty_sold) 1 15 2 30 3 45 4 15
vii. select watch_name, price, type from watches w, sale s where
watch_name price type HighFashion 7000 Unisex
viii. select watch_name, qty_store, sum(qty_sold), qty_storesum(qty_sold)
“Stock” from watches w, sale s where
w.watchid=s.watchid group by s.watchid;
watch_name qty_store qty_sold Stock HighTime 100 25 75 LifeTime 150 40 110 Wave 200 30 170 GoldenTime 100 10 90
6 (a) Correct the following boolean statements:
1. X+1 = X 2. (A')'=A' 3. A+A'=0 4. (A+B)' = A.B
1. X+1 =1 or X+0=X 2. ((A’)’) = A 3. A+A’= 1 or A.A’=0 4. (A+B)’ = A’.B’
(b) Draw the equivalent logic circuit for the following Boolean expression: (A.B)+C 1
(c) Write the POS form of a Boolean Function F, which is represented in a truth tale as follows: 2
P Q R F 0 0 0 0 0 0 1 1 0 1 0 1 0 1 1 1 1 0 0 0 1 0 1 1 1 1 0 0 1 1 1 1
(d) Reduce the following Boolean Expression using K Map: F(A, B, C, D)= (0, 1, 3, 5, 6, 7, 9, 10, 11, 13, 14, 15)
7 (a) Identify the type of topology on the basis of the following:
1. Since every node is directly connected to the server, a large amount of cable is needed which increases the installation cost of the network.
2. It has a single common data path connecting all the nodes.
1. Star Topology
2. Bus Topology
(b) Expand the following: 1
a. VOIP: Voice Over Internet Protocol
b. SMTP: Simple Mail Transfer Protocol
(c) Who is a hacker? 1
A computer enthusiast, who uses his computer programming skills to intentionally access a computer without authorization is known as hacker. A hacker accesses the computer without the intention of destroying data or maliciously harming the computer.
(d) The following is a 32 bit binary number usually represented as 4 decimal values, each representing 8 bits, in the range 0 to 255 (known as octets) separated by decimal points 220.127.116.11. What is it? What is its importance? 1
It is an IP Address.It is used to identify the computers on a network.
(e) Daniel has to share the data among various computers of his two offices branches situated in the same city. Name the network (out of LAN, WAN, PAN and MAN) which is being formed in this process. 1
(f) Rehaana Medicos Center has set up its new center in Dubai. It has four buildings as shown in the diagram given below:
Distances between various buildings are as follows: Accounts to Research Lab 55 m Accounts to Store 150 m Store to Packaging Unit 160 m Packaging Unit to Research Lab 60 m Accounts to Packaging Unit 125 m Store to Research Lab 180 m
Number of Computers Accounts 25 Research Lab 100 Store 15 Packaging Unit 60
As a network expert, provide the best possible answer for the following queries:
i) Suggest a cable layout of connections between the buildings.
ii) Suggest the most suitable place (i.e. buildings) to house the server of this organization.
The most suitable place/ building to house the server of this organization would be building Research Lab, as this building contains the maximum number of computers.
iii) Suggest the placement of the following device with justification: a) Repeater b) Hub/Switch 1
a) For layout1, since the cabling distance between Accounts to Store is quite large, so a repeater would ideally be needed along their path to avoid loss of signals during the course of data flow in this route. For layout2, since the cabling distance between Store to Research Lab is quite large, so a repeater would ideally be placed.
b) In both the layouts, a Hub/Switch each would be needed in all the buildings to interconnect the group of cables from the different computers in each building.
iv) Suggest a system (hardware/software) to prevent unauthorized access to or from the network. 1