Programming in C (4331105) - Summer 2023 Solution

Table of Contents

Question 1(a) [3 marks]
#

List any six keywords of C language.

Answer:

Table: Six Keywords in C Language

Keyword	Purpose
int	Integer data type
float	Floating-point data type
if	Conditional statement
while	Loop structure
return	Returns value from function
void	Specifies empty return type

Mnemonic: “I Feel When Running Very Ill” (int, float, while, return, void, if)

Question 1(b) [4 marks]
#

Define variable. List the rule for naming of variable in c programming.

Answer:

Variable: A named memory location used to store data that can be modified during program execution.

Table: Rules for Variable Naming in C

Rule	Example
Must begin with letter/underscore	name, _value
Can contain letters, digits, underscore	user_1, count99
No spaces or special characters	✓: total_sum, ✗: total-sum
Case sensitive	Name ≠ name
Cannot use reserved keywords	✗: int, while
Maximum 31 characters (standard)	studentRegistrationNumber

Mnemonic: “Letters Lead, No Special Keys” (begins with letter, no special chars, no keywords)

Question 1(c) [7 marks]
#

Define flowchart. Draw and Explain flowchart symbols. Write a program to calculate simple interest using below equation. I=PRN/100 Where P=Principal amount, R=Rate of interest and N=Period.

Answer:

Flowchart: A graphical representation of an algorithm that uses standard symbols to show the sequence of operations needed to solve a problem.

Table: Flowchart Symbols

Symbol	Name	Purpose
	Terminal	Start/End
	Process	Calculations
	Input/Output	Read/Display data
	Decision	Conditions
	Flow Line	Shows sequence

Simple Interest Flowchart:

flowchart TD
    A([Start]) --> B[/Input P, R, N/]
    B --> C[Calculate I = P*R*N/100]
    C --> D[/Display I/]
    D --> E([End])

Program:

#include <stdio.h>
void main()
{
    float p, r, n, i;
    
    printf("Enter principal amount: ");
    scanf("%f", &p);
    
    printf("Enter rate of interest: ");
    scanf("%f", &r);
    
    printf("Enter time period in years: ");
    scanf("%f", &n);
    
    i = (p * r * n) / 100;
    
    printf("Simple Interest = %.2f", i);
}

Mnemonic: “Please Return Nice Interest” (Principal, Rate, Number of years, Interest)

Question 1(c) OR [7 marks]
#

Define algorithm. Write algorithm for finding volume of cylinder. Write a program to read radius(R) and height(H) from user and print calculated the volume(V) of cylinder using. V=ΠR²H.

Answer:

Algorithm: A step-by-step procedure to solve a problem in a finite amount of time.

Algorithm for Cylinder Volume:

Start
Input radius (R) and height (H)
Calculate volume using formula V = π × R² × H
Display the volume
End

Diagram: Cylinder

Program:

#include <stdio.h>
void main()
{
    float radius, height, volume;
    float pi = 3.14159;
    
    printf("Enter radius of cylinder: ");
    scanf("%f", &radius);
    
    printf("Enter height of cylinder: ");
    scanf("%f", &height);
    
    volume = pi * radius * radius * height;
    
    printf("Volume of cylinder = %.2f", volume);
}

Mnemonic: “Round Hat Volume” (Radius, Height, Volume)

Question 2(a) [3 marks]
#

List out different operators supported in C programming language.

Answer:

Table: Operators in C Programming

Operator Type	Examples	Use
Arithmetic	+, -, *, /, %	Mathematical operations
Relational	<, >, ==, !=, <=, >=	Compare values
Logical	&&, \|\|, !	Combine conditions
Assignment	=, +=, -=, *=, /=	Assign values
Increment/Decrement	++, –	Increase/decrease by 1
Bitwise	&, \|, ^, ~, «, »	Bit manipulation
Conditional	?:	Short if-else

Mnemonic: “All Relationships Lead Ancestors Incrementally Beyond Conditions” (first letter of each type)

Question 2(b) [4 marks]
#

Write a program to print sum and average of 1 to 50.

Answer:

Program:

#include <stdio.h>
void main()
{
    int i, sum = 0;
    float avg;
    
    for(i = 1; i <= 50; i++)
    {
        sum = sum + i;
    }
    
    avg = (float)sum / 50;
    
    printf("Sum of numbers from 1 to 50 = %d\n", sum);
    printf("Average of numbers from 1 to 50 = %.2f", avg);
}

Process Diagram:

flowchart TD
    A([Start]) --> B[Set sum = 0]
    B --> C[Loop i from 1 to 50]
    C --> D[Add i to sum]
    D --> E{i < 50?}
    E -->|Yes| C
    E -->|No| F[Calculate avg = sum/50]
    F --> G[/Display sum and avg/]
    G --> H([End])

Mnemonic: “Summing And Dividing” (Sum, Average, Division)

Question 2(c) [7 marks]
#

Explain arithmetic & relational operators with example.

Answer:

Arithmetic Operators:

Table: Arithmetic Operators in C

Operator	Operation	Example	Result
+	Addition	5 + 3	8
-	Subtraction	7 - 2	5
*	Multiplication	4 * 3	12
/	Division	8 / 4	2
%	Modulus (Remainder)	7 % 3	1

Relational Operators:

Table: Relational Operators in C

Operator	Meaning	Example	Result
<	Less than	5 < 8	1 (true)
>	Greater than	9 > 3	1 (true)
==	Equal to	4 == 4	1 (true)
!=	Not equal to	7 != 3	1 (true)
<=	Less than or equal to	4 <= 4	1 (true)
>=	Greater than or equal to	6 >= 9	0 (false)

Code Example:

#include <stdio.h>
void main()
{
    int a = 10, b = 5;
    
    // Arithmetic operators
    printf("a + b = %d\n", a + b);   // 15
    printf("a - b = %d\n", a - b);   // 5
    printf("a * b = %d\n", a * b);   // 50
    printf("a / b = %d\n", a / b);   // 2
    printf("a %% b = %d\n", a % b);  // 0
    
    // Relational operators
    printf("a < b: %d\n", a < b);    // 0 (false)
    printf("a > b: %d\n", a > b);    // 1 (true)
    printf("a == b: %d\n", a == b);  // 0 (false)
    printf("a != b: %d\n", a != b);  // 1 (true)
}

Mnemonic: “Add Subtract Multiply Divide Remainder” (arithmetic), “Less Greater Equal Not” (relational)

Question 2(a) OR [3 marks]
#

State the difference between gets(S) and scanf("%s",S) where S is string.

Answer:

Table: Difference between gets(S) and scanf("%s",S)

Feature	gets(S)	scanf("%s",S)
Space handling	Reads spaces between words	Stops reading at space
Input termination	Ends at newline character	Ends at whitespace
Buffer overflow	Unsafe, no length check	Safer with width limit
Example behavior	“Hello World” → “Hello World”	“Hello World” → “Hello”
Security	Deprecated due to overflow risks	Better with width specifier

Mnemonic: “Gets Spaces, Scanf Stops” (gets reads spaces, scanf stops at spaces)

Question 2(b) OR [4 marks]
#

Write a program to swap two numbers.

Answer:

Program:

#include <stdio.h>
void main()
{
    int a, b, temp;
    
    printf("Enter value of a: ");
    scanf("%d", &a);
    
    printf("Enter value of b: ");
    scanf("%d", &b);
    
    printf("Before swapping: a = %d, b = %d\n", a, b);
    
    // Swapping using temp variable
    temp = a;
    a = b;
    b = temp;
    
    printf("After swapping: a = %d, b = %d", a, b);
}

Swapping Diagram:

flowchart LR
    A["a = 5"] --> |Step 1: temp = a| C["temp = 5"]
    B["b = 10"] --> |Step 2: a = b| A1["a = 10"]
    C --> |Step 3: b = temp| B1["b = 5"]

Mnemonic: “Temporary Assists Swapping” (Temp variable enables swapping)

Question 2(c) OR [7 marks]
#

Explain Logical operator and bit-wise operator with example.

Answer:

Logical Operators:

Table: Logical Operators in C

Operator	Description	Example	Result
&&	Logical AND	(5>3) && (8>6)	1 (both true)
\|\|	Logical OR	(5<3) \|\| (8>6)	1 (one true)
!	Logical NOT	!(5>3)	0 (inverts true to false)

Bitwise Operators:

Table: Bitwise Operators in C

Operator	Description	Example	Binary Result
&	Bitwise AND	5 & 3	101 & 011 = 001 (1)
\|	Bitwise OR	5 \| 3	101 \| 011 = 111 (7)
^	Bitwise XOR	5 ^ 3	101 ^ 011 = 110 (6)
~	Bitwise NOT	~5	~0101 = 1010 (-6)
«	Left Shift	5 « 1	101 « 1 = 1010 (10)
»	Right Shift	5 » 1	101 » 1 = 10 (2)

Code Example:

#include <stdio.h>
void main()
{
    int a = 5, b = 3;
    
    // Logical operators
    printf("a>3 && b<5: %d\n", (a>3) && (b<5));  // 1 (true)
    printf("a<3 || b>1: %d\n", (a<3) || (b>1));  // 1 (true)
    printf("!(a>b): %d\n", !(a>b));              // 0 (false)
    
    // Bitwise operators
    printf("a & b: %d\n", a & b);   // 1
    printf("a | b: %d\n", a | b);   // 7
    printf("a ^ b: %d\n", a ^ b);   // 6
    printf("~a: %d\n", ~a);         // -6
    printf("a << 1: %d\n", a << 1); // 10
    printf("a >> 1: %d\n", a >> 1); // 2
}

Mnemonic: “AND OR NOT” (logical operators), “AND OR XOR NOT SHIFT” (bitwise operators)

Question 3(a) [3 marks]
#

Explain multiple if-else statement with example.

Answer:

Multiple if-else: Series of if-else statements where each condition is checked sequentially until a true condition is found.

Structure:

if (condition1)
    statement1;
else if (condition2)
    statement2;
else if (condition3)
    statement3;
else
    default_statement;

Code Example:

#include <stdio.h>
void main()
{
    int marks;
    
    printf("Enter marks: ");
    scanf("%d", &marks);
    
    if (marks >= 80)
        printf("Grade: A");
    else if (marks >= 70)
        printf("Grade: B");
    else if (marks >= 60)
        printf("Grade: C");
    else if (marks >= 50)
        printf("Grade: D");
    else
        printf("Grade: F");
}

Diagram:

flowchart TD
    A[Start] --> B{marks >= 80?}
    B -->|Yes| C[Grade A]
    B -->|No| D{marks >= 70?}
    D -->|Yes| E[Grade B]
    D -->|No| F{marks >= 60?}
    F -->|Yes| G[Grade C]
    F -->|No| H{marks >= 50?}
    H -->|Yes| I[Grade D]
    H -->|No| J[Grade F]

Mnemonic: “Check Each Condition in Sequence” (CECS)

Question 3(b) [4 marks]
#

State the working of while loop and for loop.

Answer:

Table: While Loop vs For Loop

Feature	While Loop	For Loop
Syntax	`while(condition) { statements; }`	`for(init; condition; update) { statements; }`
When to use	When number of iterations is unknown	When number of iterations is known
Initialization	Before the loop	Inside the loop declaration
Update	Must be done inside the loop body	Automatically in loop declaration
Exit control	Only at the beginning	Only at the beginning
Example	Validating user input	Iterating fixed number of times

While Loop Flow:

flowchart TD
    A([Start]) --> B[Initialize]
    B --> C{Condition}
    C -->|True| D[Body]
    D --> C
    C -->|False| E([End])

For Loop Flow:

flowchart TD
    A([Start]) --> B[Initialize]
    B --> C{Condition}
    C -->|True| D[Body]
    D --> E[Update]
    E --> C
    C -->|False| F([End])

Mnemonic: “While Checks Then Acts” (WCTA), “For Initializes Tests Updates” (FITU)

Question 3(c) [7 marks]
#

Write a program to find factorial of a given number.

Answer:

Program:

#include <stdio.h>
void main()
{
    int num, i;
    unsigned long fact = 1;
    
    printf("Enter a number: ");
    scanf("%d", &num);
    
    if (num < 0)
        printf("Factorial not defined for negative numbers");
    else
    {
        for(i = 1; i <= num; i++)
        {
            fact = fact * i;
        }
        printf("Factorial of %d = %lu", num, fact);
    }
}

Factorial Calculation Table: For example, if num = 5:

Iteration	i	fact = fact * i	New fact value
Initial	-	-	1
1	1	1 * 1	1
2	2	1 * 2	2
3	3	2 * 3	6
4	4	6 * 4	24
5	5	24 * 5	120

Factorial Calculation Diagram:

flowchart TD
    A([Start]) --> B[/Input num/]
    B --> C{num < 0?}
    C -->|Yes| D[/Error message/]
    C -->|No| E[fact = 1]
    E --> F[Loop i from 1 to num]
    F --> G[fact = fact * i]
    G --> H{i < num?}
    H -->|Yes| F
    H -->|No| I[/Display fact/]
    I --> J([End])

Mnemonic: “Find And Count The Numbers!” (FACTN! - Factorial)

Question 3(a) OR [3 marks]
#

Explain the working of switch-case statement with example.

Answer:

Switch-Case: A selection statement that allows a variable to be tested for equality against a list of values (cases).

Structure:

switch(expression) {
    case value1:
        statements1;
        break;
    case value2:
        statements2;
        break;
    default:
        default_statements;
}

Code Example:

#include <stdio.h>
void main()
{
    int day;
    
    printf("Enter day number (1-7): ");
    scanf("%d", &day);
    
    switch(day) {
        case 1:
            printf("Monday");
            break;
        case 2:
            printf("Tuesday");
            break;
        case 3:
            printf("Wednesday");
            break;
        case 4:
            printf("Thursday");
            break;
        case 5:
            printf("Friday");
            break;
        case 6:
            printf("Saturday");
            break;
        case 7:
            printf("Sunday");
            break;
        default:
            printf("Invalid day");
    }
}

Switch-Case Diagram:

flowchart TD
    A[Start] --> B[/Input day/]
    B --> C{Switch day}
    C -->|case 1| D[Monday]
    C -->|case 2| E[Tuesday]
    C -->|case 3| F[Wednesday]
    C -->|case 4| G[Thursday]
    C -->|case 5| H[Friday]
    C -->|case 6| I[Saturday]
    C -->|case 7| J[Sunday]
    C -->|default| K[Invalid day]
    D & E & F & G & H & I & J & K --> L[End]

Mnemonic: “Select Value, Exit with Break” (SVEB)

Question 3(b) OR [4 marks]
#

State the use of break and continue keyword.

Answer:

Table: Break vs Continue Keywords

Feature	break	continue
Purpose	Exits from current loop/switch	Skips current iteration, continues next iteration
Effect on loop	Terminates the loop	Proceeds to next iteration
Where used	Loops & switch statements	Only in loops
Control flow	Passes to statement after loop	Goes to loop condition check
Example use	Exit loop when condition met	Skip specific iterations

Flow Diagram - break:

flowchart TD
    A([Start]) --> B[Loop]
    B --> C{Condition}
    C -->|True| D[break]
    C -->|False| E[Loop statements]
    E --> B
    D --> F[Statements after loop]
    F --> G([End])

Flow Diagram - continue:

flowchart TD
    A([Start]) --> B[Loop]
    B --> C{Condition}
    C -->|True| D[continue]
    C -->|False| E[Loop statements]
    D --> B
    E --> B
    B -->|Loop ends| F([End])

Mnemonic: “Break Exits, Continue Skips” (BECS)

Question 3(c) OR [7 marks]
#

Write a program to read number of lines (n) from keyboard and print the triangle shown below. For Example, n=5

Answer:

Program:

#include <stdio.h>
void main()
{
    int n, i, j;
    
    printf("Enter number of lines: ");
    scanf("%d", &n);
    
    for(i = n; i >= 1; i--)
    {
        for(j = 1; j <= i; j++)
        {
            printf("%d ", j);
        }
        printf("\n");
    }
}

Pattern Logic Table: For n = 5:

i	j	Output
5	j=1 to 5	1 2 3 4 5
4	j=1 to 4	1 2 3 4
3	j=1 to 3	1 2 3
2	j=1 to 2	1 2
1	j=1 to 1	1

Pattern Visualization:

Program Flow:

flowchart TD
    A([Start]) --> B[/Input n/]
    B --> C[outer loop: i = n to 1]
    C --> D[inner loop: j = 1 to i]
    D --> E[/Print j/]
    E --> F{j < i?}
    F -->|Yes| D
    F -->|No| G[/Print newline/]
    G --> H{i > 1?}
    H -->|Yes| C
    H -->|No| I([End])

Mnemonic: “Decreasing Rows With Increasing Values” (DRWIV)

Question 4(a) [3 marks]
#

Explain nested if-else statement with example.

Answer:

Nested if-else: An if-else statement inside another if or else block.

Structure:

if (condition1) {
    if (condition2) {
        statements1;
    } else {
        statements2;
    }
} else {
    statements3;
}

Code Example:

#include <stdio.h>
void main()
{
    int age, weight;
    
    printf("Enter age: ");
    scanf("%d", &age);
    
    if (age >= 18) {
        printf("Enter weight: ");
        scanf("%d", &weight);
        
        if (weight >= 50) {
            printf("Eligible to donate blood");
        } else {
            printf("Underweight, not eligible");
        }
    } else {
        printf("Age below 18, not eligible");
    }
}

Nested if-else Diagram:

flowchart TD
    A[Start] --> B{age >= 18?}
    B -->|Yes| C{weight >= 50?}
    B -->|No| D[Not eligible: Age]
    C -->|Yes| E[Eligible]
    C -->|No| F[Not eligible: Weight]
    D & E & F --> G[End]

Mnemonic: “Check Outside Then Inside” (COTI)

Question 4(b) [4 marks]
#

Write a program to exchange two integer numbers using pointer arguments.

Answer:

Program:

#include <stdio.h>
void main()
{
    int a, b, temp;
    int *p1, *p2;
    
    printf("Enter value of a: ");
    scanf("%d", &a);
    
    printf("Enter value of b: ");
    scanf("%d", &b);
    
    p1 = &a;  // p1 points to a
    p2 = &b;  // p2 points to b
    
    printf("Before swapping: a = %d, b = %d\n", a, b);
    
    // Swapping using pointers
    temp = *p1;
    *p1 = *p2;
    *p2 = temp;
    
    printf("After swapping: a = %d, b = %d", a, b);
}

Pointer Swapping Diagram:

Mnemonic: “Pointers Exchange Memory Values” (PEMV)

Question 4(c) [7 marks]
#

Define Array. Explain initialization & declaration of one-dimensional array.

Answer:

Array: A collection of elements of the same data type stored in contiguous memory locations and accessed using indices.

Table: Array Declaration & Initialization

Operation	Syntax	Example
Declaration	data_type array_name[size];	int marks[5];
Initialization at declaration	data_type array_name[size] = {values};	int nums[4] = {10, 20, 30, 40};
Partial initialization	data_type array_name[size] = {values};	int nums[5] = {10, 20};
Without size	data_type array_name[] = {values};	int nums[] = {10, 20, 30};
Individual element	array_name[index] = value;	marks[0] = 95;

Code Example:

#include <stdio.h>
void main()
{
    // Declaration
    int marks[5];
    
    // Initialization after declaration
    marks[0] = 85;
    marks[1] = 90;
    marks[2] = 78;
    marks[3] = 92;
    marks[4] = 88;
    
    // Declaration with initialization
    int scores[] = {95, 89, 76, 82, 91};
    
    // Accessing array elements
    printf("marks[2] = %d\n", marks[2]);
    printf("scores[3] = %d", scores[3]);
}

Array Representation:

Memory Representation:

flowchart LR
    A["marks[0]
85"] --- B["marks[1]
90"]
    B --- C["marks[2]
78"]
    C --- D["marks[3]
92"]
    D --- E["marks[4]
88"]

Mnemonic: “Declare, Initialize, Access With Index” (DIAWI)

Question 4(a) OR [3 marks]
#

Explain do while loop with example.

Answer:

do-while loop: A loop that executes the body at least once before checking the condition.

Structure:

do {
    statements;
} while(condition);

Code Example:

#include <stdio.h>
void main()
{
    int num, sum = 0;
    
    do {
        printf("Enter a number (0 to stop): ");
        scanf("%d", &num);
        sum += num;
    } while(num != 0);
    
    printf("Sum of entered numbers = %d", sum);
}

do-while Loop Flow:

flowchart TD
    A([Start]) --> B[Body statements]
    B --> C{Condition}
    C -->|True| B
    C -->|False| D([End])

Key Differences from while loop:

Body executes at least once
Condition checked after execution
Semicolon required after condition

Mnemonic: “Do First, Check Later” (DFCL)

Question 4(b) OR [4 marks]
#

Explain following functions with example: (1) gets() (2) puts() (3) strlen() (4) strcpy()

Answer:

Table: String Functions in C

Function	Purpose	Syntax	Example
gets()	Reads string with spaces	gets(string);	gets(name);
puts()	Displays string with newline	puts(string);	puts(name);
strlen()	Returns string length	strlen(string);	n = strlen(name);
strcpy()	Copies source to destination	strcpy(dest, src);	strcpy(str1, str2);

Code Example:

#include <stdio.h>
#include <string.h>
void main()
{
    char name[50], copy[50];
    int length;
    
    printf("Enter your name: ");
    gets(name);           // Read name with spaces
    
    puts("Your name is:"); // Display with newline
    puts(name);
    
    length = strlen(name); // Get string length
    printf("Length: %d\n", length);
    
    strcpy(copy, name);    // Copy name to copy
    printf("Copied string: %s", copy);
}

Mnemonic: “Gets Puts String’s Length and Copies” (GPSLC)

Question 4(c) OR [7 marks]
#

Define recursion and explain with suitable example. Write a program to find factorial of a given number using recursion.

Answer:

Recursion: A process where a function calls itself directly or indirectly until a specific condition is met.

Recursion Components:

Base case: Condition to stop recursion
Recursive case: Function calling itself

Code Example:

#include <stdio.h>

// Recursive function to find factorial
unsigned long factorial(int n)
{
    // Base case
    if (n == 0 || n == 1)
        return 1;
    
    // Recursive case
    else
        return n * factorial(n-1);
}

void main()
{
    int num;
    unsigned long result;
    
    printf("Enter a number: ");
    scanf("%d", &num);
    
    if (num < 0)
        printf("Factorial not defined for negative numbers");
    else
    {
        result = factorial(num);
        printf("Factorial of %d = %lu", num, result);
    }
}

Recursive Factorial Calculation: For factorial(5)

Table: Recursion Trace

Call	Returns	Calculation
factorial(5)	5 × factorial(4)	5 × 24 = 120
factorial(4)	4 × factorial(3)	4 × 6 = 24
factorial(3)	3 × factorial(2)	3 × 2 = 6
factorial(2)	2 × factorial(1)	2 × 1 = 2
factorial(1)	1	Base case

Recursion Diagram:

flowchart TD
    A["factorial(5)"] --> B["5 * factorial(4)"]
    B --> C["4 * factorial(3)"]
    C --> D["3 * factorial(2)"]
    D --> E["2 * factorial(1)"]
    E --> F["return 1"]
    F --> G["return 2"]
    G --> H["return 6"]
    H --> I["return 24"]
    I --> J["return 120"]

Mnemonic: “Function Calling Itself, Bottoming Out” (FCIBO)

Question 5(a) [3 marks]
#

Write the difference between array and structure.

Answer:

Table: Array vs Structure

Feature	Array	Structure
Data type	Same data type for all elements	Can store different data types
Access	Using index (arr[0])	Using member name (s.name)
Memory allocation	Contiguous	Contiguous but different sizes
Size	Fixed size at declaration	Sum of sizes of all members
Purpose	Collection of similar items	Grouping related data of different types
Declaration	`int arr[5];`	`struct student { int id; char name[20]; };`

Diagram:

flowchart LR
    subgraph Array
    A["[0]
int"] --- B["[1]
int"] --- C["[2]
int"]
    end
    
    subgraph Structure
    D["id
int"] --- E["name
char[]"] --- F["age
int"]
    end

Mnemonic: “Arrays for Same, Structures for Different” (ASSD)

Question 5(b) [4 marks]
#

Write a C program using array that find the maximum value from given 10 values.

Answer:

Program:

#include <stdio.h>
void main()
{
    int arr[10], i, max;
    
    // Input 10 values
    printf("Enter 10 values:\n");
    for(i = 0; i < 10; i++)
    {
        printf("Enter value %d: ", i+1);
        scanf("%d", &arr[i]);
    }
    
    // Find maximum value
    max = arr[0];  // Assume first element is maximum
    for(i = 1; i < 10; i++)
    {
        if(arr[i] > max)
            max = arr[i];
    }
    
    printf("Maximum value is: %d", max);
}

Algorithm Flow:

flowchart TD
    A([Start]) --> B[/Input 10 values/]
    B --> C[Set max = first element]
    C --> D[Loop i from 1 to 9]
    D --> E{arr[i] > max?}
    E -->|Yes| F[max = arr[i]]
    E -->|No| G[Continue]
    F & G --> H{i < 9?}
    H -->|Yes| D
    H -->|No| I[/Display max/]
    I --> J([End])

Mnemonic: “Compare And Replace Maximum” (CARM)

Question 5(c) [7 marks]
#

Define structure? Develop a structure named book to save following information about books. Book title, Name of author, Price and Number of pages.

Answer:

Structure: A user-defined data type that groups related variables of different data types under a single name.

Book Structure Code:

#include <stdio.h>

struct book {
    char title[50];
    char author[30];
    float price;
    int pages;
};

void main()
{
    struct book b1;
    
    // Input book details
    printf("Enter book title: ");
    gets(b1.title);
    
    printf("Enter author name: ");
    gets(b1.author);
    
    printf("Enter price: ");
    scanf("%f", &b1.price);
    
    printf("Enter number of pages: ");
    scanf("%d", &b1.pages);
    
    // Display book details
    printf("\nBook Details:\n");
    printf("Title: %s\n", b1.title);
    printf("Author: %s\n", b1.author);
    printf("Price: Rs. %.2f\n", b1.price);
    printf("Pages: %d", b1.pages);
}

Structure Memory Representation:

Structure Diagram:

classDiagram
    class book {
        char title[50]
        char author[30]
        float price
        int pages
    }

Mnemonic: “Title Author Price Pages” (TAPP)

Question 5(a) OR [3 marks]
#

What is a string? What are the operations that can be performed on string?

Answer:

String: A sequence of characters terminated by a null character ‘\0’.

Table: String Operations in C

Operation	Function	Example
Input	gets(), scanf()	gets(str), scanf("%s", str)
Output	puts(), printf()	puts(str), printf("%s", str)
Length	strlen()	len = strlen(str)
Copy	strcpy()	strcpy(dest, src)
Concatenate	strcat()	strcat(str1, str2)
Compare	strcmp()	result = strcmp(str1, str2)
Search	strchr(), strstr()	ptr = strchr(str, ‘a’)
Convert	strlwr(), strupr()	strlwr(str), strupr(str)

String Representation:

Mnemonic: “Input Output Length Copy Concat Compare Search Convert” (IOLCCSC)

Question 5(b) OR [4 marks]
#

Write a program prints its ASCII value from A to Z.

Answer:

Program:

#include <stdio.h>
void main()
{
    char ch;
    
    printf("ASCII values from A to Z:\n");
    printf("Character\tASCII Value\n");
    printf("-----------------------\n");
    
    for(ch = 'A'; ch <= 'Z'; ch++)
    {
        printf("    %c\t\t   %d\n", ch, ch);
    }
}

Sample Output Table:

Character	ASCII Value
A	65
B	66
…	…
Z	90

ASCII Chart Representation:

Mnemaid: “Alphabets Sequentially Creating Integer Indices” (ASCII)

Question 5(c) OR [7 marks]
#

What is user defined and library function? Explain with two examples of each.

Answer:

Library Functions: Pre-defined functions provided by C language that are ready to use.

User-Defined Functions: Functions created by the programmer to perform specific tasks.

Table: Library vs User-Defined Functions

Feature	Library Functions	User-Defined Functions
Definition	Pre-defined in header files	Created by programmer
Declaration	No need to define	Must be defined
Examples	printf(), scanf(), strlen()	calculateArea(), findMax()
Header files	stdio.h, string.h, math.h, etc.	No header required
Purpose	Common tasks	Customized tasks

Examples of Library Functions:

strlen() - String Length

#include <stdio.h>
#include <string.h>
void main()
{
    char str[] = "Hello";
    int length = strlen(str);  // Library function
    printf("Length of string: %d", length);
}

sqrt() - Square Root

#include <stdio.h>
#include <math.h>
void main()
{
    float num = 25, result;
    result = sqrt(num);  // Library function
    printf("Square root of %.0f = %.2f", num, result);
}

Examples of User-Defined Functions:

calculateArea() - Area of Rectangle

#include <stdio.h>

// User-defined function
float calculateArea(float length, float width)
{
    return length * width;
}

void main()
{
    float length = 10.5, width = 5.5, area;
    area = calculateArea(length, width);  // User function call
    printf("Area of rectangle = %.2f", area);
}

findMax() - Maximum of Three Numbers

#include <stdio.h>

// User-defined function
int findMax(int a, int b, int c)
{
    if(a >= b && a >= c)
        return a;
    else if(b >= a && b >= c)
        return b;
    else
        return c;
}

void main()
{
    int x = 10, y = 25, z = 15, max;
    max = findMax(x, y, z);  // User function call
    printf("Maximum number is: %d", max);
}