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GNDU Question Paper-2021

B.A 2

nd

Semester

COMPUTER SCIENCE

1. (a) What do you understand by Number System ? Convert (725.55) into Binary, Octal

and Hexadecimal Number Systems.

(b) Explain the concept of Pseudo Code by taking suitable example.

2. (a) Explain various data types supported by C Programming Language giving suitable

examples.

(b) How Constant is different from Variable ? Explain the use of String Constants using

suitable example.

3. Explain the use of the following operators using suitable examples:

(a) Arithmetic Operators

5. (a) Discuss the use of different forms of If-else statement using suitable example.

(b) What is the purpose of Continue statement ? Explain its use. Compare it with break

statement.

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6. What is Function? What are differences between passing an array to a function and

passing a single-valued data item to a function? Explain using example.

7. (a) Explain the use of pointers in Call by Less Reference parameter passing for functions

using example.

(b) Write a program using pointers to swap the values of two integer numbers.

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B.A 2

nd

Semester

COMPUTER SCIENCE

1. (a) What do you understand by Number System ? Convert (725.55) into Binary, Octal

and Hexadecimal Number Systems.

(b) Explain the concept of Pseudo Code by taking suitable example.

Ans: Understanding Number Systems as a Fun Story

Imagine you're part of a secret club, and this club has four secret codes to write numbers.

Each code is a different "language" to express numbers, and you’re about to become a pro

at decoding and translating these! The four most important languages in our secret club are:

systems. To do this, we’ll break the number into two parts:

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We’ll convert each part separately.

1. Converting Decimal to Binary (Base 2)

Step 1: Convert the whole number 725 to Binary

To convert a decimal whole number to binary:

Conversion:

Binary of 725: 1011010101

Step 2: Convert the fractional part 0.55 to Binary

For fractions, multiply the fraction by 2 and note the integer part. Continue with the

fractional part until you get 0 or reach a satisfactory precision.

Conversion:

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Binary of 0.55: 0.100011...

Final Binary: 1011010101.100011...

2. Converting Decimal to Octal (Base 8)

Step 1: Convert the whole number 725 to Octal

For octal, divide the whole number by 8 instead of 2.

Conversion:

Octal of 0.55: 0.43146...

Final Octal: 1325.43146...

Step 1: Convert the whole number 725725725 to Hexadecimal

For hexadecimal, divide by 16.

Conversion:

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Hexadecimal of 725: 2D5

Step 2: Convert the fractional part 0.550.550.55 to Hexadecimal

For fractions, multiply by 16 and note the integer part.

Conversion:

Hexadecimal of 0.55: 0.8C...

Final Hexadecimal: 2D5.8C...

Always divide the whole part and multiply the fractional part to switch between languages.

With practice, you'll become fluent in all four number systems!

(b) What is Pseudo Code?

Pseudo code is like writing a recipe for your computer before you cook (write the actual

program in C or any other language). It’s not written in a real programming language like C,

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Think of pseudo code as a bridge between your brain (where ideas form) and the computer

(which needs code to run).

A Fun Analogy: Cooking Pasta

Let’s say you want to make pasta. You’re not writing a cookbook yet, just jotting down steps

in your notebook for practice. Here’s how your pseudo code might look:

Notice how these steps aren’t written in a specific language but are clear enough to follow?

That’s pseudo code!

Example: Pseudo Code for a Real Program

Now let’s connect it to programming. Imagine you’re building a program that calculates the

When you write this in C, it would look like this:

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Steps to Write Good Pseudo Code (Just Like Writing a Great Recipe)

Problem: You’re designing a program to tell if a number is odd or even.

Here’s the pseudo code:

C Code Translation:

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A Fun Twist: Pseudo Code for Morning Routine

Imagine you want to create a "program" for your morning routine. Here’s the pseudo

code:

before diving into code. Just like you wouldn’t start cooking without planning your recipe,

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Imagine a bakery. The bakery has:

So, in the bakery:

More on Strings in C

Strings in C are stored as arrays of characters. For example:

#include <stdio.h>

#include <string.h>

int main() {

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char name1[] = "Alice";

char name2[] = "Bob";

// Comparing strings

if (strcmp(name1, name2) == 0) {

printf("The names are the same.\n");

} else {

printf("The names are different.\n");

}

By thinking of constants as the strict guardians and variables as the friendly helpers, you’ll

never forget how they work. And remember: strings are just words stored in magical boxes

(a) Arithmetic Operators

the Arithmetic Wizards. These wizards could add, subtract, multiply, divide, and even find

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Let’s dive deeper into their powers and how they work.

Arithmetic Wizards (Arithmetic Operators) 󼘆󼘇󼙂󼛌󼛍󼛎󼙄󼙅󼛏󼙆󼙇󼙈󼘐󼛐󼘑󼛑󼘒󼛒󼛓󼛔󼘓󼘗󼘘󼘜󼛕󼘙󼘚󼘛

The Arithmetic Wizards are responsible for performing basic math operations. They work

with two numbers at a time (called operands). Think of them like chefs who mix two

Story Connection: Addus loves pairing apples. If you give him 5 apples and 3 apples, he’ll

give you a basket with 8 apples.

int a = 5, b = 3;

int result = a - b; // result = 2

Story Connection: Subby loves taking apples away. If you have 5 apples and he takes away

int a = 6, b = 3;

int result = a / b; // result = 2

Story Connection: Divider loves sharing apples equally. If you have 6 apples and 3 friends,

each gets 2 apples.

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Note: Be careful! Divider doesn’t like dividing by 0. If you try, he gets angry and causes an

error. 󺠣󺠤󺠥󺠦󺠧󺠨

int a = 7, b = 3;

int a = +5; // a = 5

Story Connection: Positive Wizard just smiles and says, “Keep it positive!”

int a = 5;

int b = -a; // b = -5

Story Connection: Negative Wizard turns things upside down. If you have 5 apples, she’ll

magically turn them into -5 apples (debt).

you visit her.

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Fun Fact:

Increasy can work in two ways:

o Post-Increment (a++): First uses the number, then increments it.

Example:

int a = 5;

int b = a++; // b = 5, a = 6

Example:

int a = 5;

a--; // a = 4

Story Connection: Decreasy is like a borrower. She takes away one apple each time you visit

her.

Fun Fact:

Example:

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Example Code:

#include <stdio.h>

int main() {

int x = 10, y = 3;

// Arithmetic Wizards in Action

printf("Addition: %d\n", x + y); // 13

printf("Subtraction: %d\n", x - y); // 7

printf("Negative: %d\n", -x); // -10

printf("Increment (Post): %d\n", x++); // 10, then x becomes 11

printf("Increment (Pre): %d\n", ++x); // 12

printf("Decrement (Post): %d\n", x--); // 12, then x becomes 11

printf("Decrement (Pre): %d\n", --x); // 10

return 0;

Output:

Addition: 13

Subtraction: 7

Multiplication: 30

Division: 3

Modulus: 1

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Positive: 10

Negative: -10

Increment (Post): 10

Increment (Pre): 12

Decrement (Post): 12

Decrement (Pre): 10

Wrapping Up the Tale

The Arithmetic and Unary Wizards work tirelessly in the land of C Programming to solve

4. (a) Explain the use of gets() and puts() using suitable example.

help me make a program that takes a sentence from the user and shows it back to them?

But please explain it simply, so I can remember forever!”

The two friends, gets() and puts(), smiled and said, “Sure! That’s what we’re here for!”

Meet gets(): The Listener 󹴮󹴯󹴰󹴱󹴲󹴳

gets() is like a kind and patient listener. Its job is to take a complete line of text (a string)

sentence until the user presses the Enter key.

Imagine you're writing a letter, and gets() is your assistant. You dictate the entire line, and it

writes it down neatly, just as you say it.

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How gets() Works:

Example of gets():

#include <stdio.h>

int main() {

char name[50]; // A place to store the input (string).

return 0;

}

Output of the Program:

Enter your name: Harry Potter

Nice to meet you, Harry Potter

Here’s what happened:

Meet puts(): The Storyteller 󹵪󹵧󹵨󹵩

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Think of puts() as your friend who loves to announce things loudly and clearly. Once you

give it something to say, it says it, loud and proud, followed by a little pause (a new line).

How puts() Works:

return 0;

}

Welcome to C Programming!

Notice how puts() automatically added a new line after displaying the message.

The gets() and puts() Duo in Action 󷗛󷗜

Let’s create a fun little program where both gets() and puts() work together to make things

happen!

Example: A Friendly Chatbot

#include <stdio.h>

int main() {

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printf("What's your name? ");

gets(userName);

// Greeting the user

printf("Hello, ");

puts(userName);

// Asking for the user's favorite food

printf("What’s your favorite food? ");

return 0;

}

Output of the Program:

What's your name? Alice Wonderland

Hello, Alice Wonderland

What’s your favorite food? Pizza

Yum! I love Pizza

it can cause errors or unexpected behavior.

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printf("Wait at the crossroads.\n");

}

Here, IF checks one condition at a time. If none of the conditions are true, Charlie stays put.

4. Nested IF-ELSE

The Scenario: A new traveler arrives with an even more complicated problem. "If it’s sunny,

I’ll take the right path. But if it’s sunny and windy, I’ll wait under the tree. If it rains, I’ll use

In programming:

if (isSunny) {

if (isWindy) {

printf("Wait under the tree.\n");

} else {

printf("Take the sunny path.\n");

}

decisions.

5. Switch-Case Statement (A Cousin of IF-ELSE)

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switch (favoriteColor) {

case 'R':

printf("Take the right path.\n");

break;

case 'B':

printf("Take the left path.\n");

break;

case 'G':

printf("Go straight.\n");

Complete Example: Choosing a Snack at the Crossroads

Let’s say a traveler has these options:

The program:

#include <stdio.h>

int main() {

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int isHungry = 1; // 1 means true

char snackPreference = 'S'; // 'S' for sweet, 'T' for salty

if (isHungry) {

if (snackPreference == 'S') {

printf("Here’s a candy bar.\n");

} else if (snackPreference == 'T') {

printf("Here’s a pack of chips.\n");

}

In Real Life

Think of IF-ELSE as how you make daily decisions:

Programming with IF-ELSE is just writing these decisions in code for computers to follow. It’s

like giving instructions to a robot!

Recap of the Story

By guiding travelers through their dilemmas, the wise villager and his companion showed us

the magic of decision-making in programming. Just like travelers at a crossroads, programs

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(b) The Purpose of the Continue Statement and its Use – Explained in a Fun and Simple

Story!

Ans: Imagine you’re playing a treasure hunt game with your friends. Your goal is to collect as

many treasures as possible by visiting a series of checkpoints. However, at some

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The Villain of the Story: Obstacles That Break the Game

Now, imagine a dangerous trap in your treasure hunt game. If you land on this trap, the

game is over. Similarly, in programming, the break statement is used to stop the loop

entirely. It’s like saying:

Here’s an example to understand the break statement. Suppose you’re checking numbers

for (int i = 1; i <= 10; i++) {

if (i == 5) {

break; // Exit the loop when i is 5

}

printf("%d\n", i); // Print the number

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Output:

1

3

5

7

9

Here, the continue statement helps us ignore even numbers and print only odd ones.

Why Use the Break Statement?

The break statement is helpful when:

int target = 6;

for (int i = 0; i < 5; i++) {

if (numbers[i] == target) {

printf("Found %d at index %d\n", target, i);

break; // Stop searching once the target is found

}

return 0;

}

Output:

Found 6 at index 2

Here, the break statement helps stop the loop as soon as the number 6 is found.

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The Moral of the Story

Think of continue as a "skip" button and break as a "stop" button:

6. What is Function? What are differences between passing an array to a function and

manageable parts, making the code easier to read, maintain, and reuse.

Imagine a function as a machine. For instance, a washing machine is designed to wash

clothes. When you want to use it, you give it inputs (like clothes, detergent, and water), and

it performs its task (washing the clothes). Similarly, in programming, a function may take

some input, process it, and then give an output.

Key Points about Functions:

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Let’s explore the differences between these two approaches.

Passing a Single-valued Data Item to a Function

When you pass a single-valued data item (e.g., an integer, character, or floating-point value)

to a function, only one value is sent to the function. This value can either be copied or

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Example:

Let’s write a program to double the values in an array:

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cout << "Box A = " << a << ", Box B = " << b << endl;

return 0;

}

Step-by-Step Explanation of the Code

1. Function Definition: The Swap Spell

void swap(int* x, int* y)

3. Swapping the Values

*y = temp;

4. Using the Function

swap(&a, &b);

Input and Output

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Example Output:

Before swapping:

Box A = 5, Box B = 10

After swapping:

Box A = 10, Box B = 5

Why Use Pointers?

Pointers make swapping more efficient because:

A Practice Challenge

o Using temporary storage.

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8. (a) What is Structure? How it is different from an array? How can a structure member

be accessed? Explain using suitable example.

(b) Explain the concept of Union. In what way does the initialization of a union variable

differ from the initialization of a structure variable?

Ans: The Story of Arrays and Structures

Once upon a time in the world of programming, there were two friends, Array and Structure. They

Meet Array: The Organized Family

Here's an example of an array:

int numbers[5] = {10, 20, 30, 40, 50};

Here, the "neighborhood" has five houses, each holding an integer value.

Meet Structure: The Multitalented Team

Structure, on the other hand, was like a team of superheroes where each member had a unique

superpower. This team could have a doctor, a teacher, a firefighter, and a scientist—all working

together under one team name. Unlike the array family, Structure allowed diversity.

In programming terms:

};

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Here, the "team" is called Person, and it has three members:

Key Differences Between Array and Structure

Accessing Structure Members

To access a structure’s members, you need to use the dot operator (.). Think of it as asking a specific

superhero about their skill.

Let’s create and use the Person structure:

#include <stdio.h>

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}

Fun Scenario: Comparing Array and Structure

Imagine you’re organizing data for your school:

int marks[30];

Each student’s marks are stored in consecutive slots, like marks[0], marks[1], and so on.

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struct Student {

};

struct Student s1;

You can store all the data about one student (s1) in one place, with each piece of data being

};

c

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Conclusion: Arrays and Structures Together

Sometimes, you might need both Arrays and Structures to solve a problem. For example, if you want