1.
Functions – 5 Marks
In C, a function is a set of statements grouped together to perform a specific task, promoting
modularity and code reusability. Functions are defined with a specific syntax:
Example :
Key Components :
1. Function Prototype: Declares the function (e.g., int sum(int, int);).
2. Function Definition: Contains the code (e.g., int sum(int a, int b) { return a + b; }).
3. Function Call: Executes the function (e.g., sum(10, 20);).
4. Return Statement: Returns a value (e.g., return a + b;).
2. Categories – 5 Marks
In C programming, functions can be categorized into four types based on their arguments and
return values. These categories are:
1. Function without Arguments and without a Return Value:
This function neither takes input nor returns any value. It performs a task independently. For
example:
Here, displayMessage() simply prints a message without requiring input or returning output.
2. Function with Arguments and without a Return Value:
This function Takes input, no output.Example:
5. Here, displaySum() takes two integers and prints their sum.
3. Function without Arguments and with a Return Value:
This function does not take input but returns output. Example:
6. Here, getFive() returns the integer 5 without needing any arguments.
4. Function with Arguments and with a Return Value:
This function takes Takes input & returns output. Example:
7. Here, sum() takes two integers, adds them, and returns the result.
3. Introduction to Memory Management (5 Marks)
Memory management in C involves allocating and managing memory for variables during program
execution. It uses storage classes and pointers to control scope, lifetime, and access.
Storage Classes:
o Automatic (auto): Local to a block, destroyed after execution (e.g., auto int x;).
o External (extern): Global, shared across files (e.g., extern int a;).
o Static: Retains value across calls, local/global scope (e.g., static int count = 0;).
o Register: Stored in CPU registers for speed (e.g., register int i;).
Variables:
o Local: Limited to a function (e.g., int x = 5; inside main()).
o Global: Accessible throughout the program (e.g., int a = 20; outside functions).
Example :
4. Array of Structures - 5 Marks
An array of structures in C allows storing multiple instances of a structure under a single name.
Each element is a structure with its own members.
Syntax:
8. Accessing: Use the dot operator (.) for members (e.g., array[i].member).
Example :-
9. Use: Ideal for managing related data (e.g., student records).
1. Recursion - 2 Marks
Recursion in C occurs when a function calls itself to solve a problem by breaking it into smaller
instances. The document mentions a recursive example with a base condition (n == 0) and a
recursive case (n + sum(n-1)). For instance, a function to calculate the sum of numbers from 1 to
n:
2. Nesting Function - 2 Marks
In C, nesting of functions refers to calling one function from within another, not defining a function
inside another (which isn’t allowed). The document explains this with an example:
3. Nested Structures (2 Marks)
Nested structures in C involve defining one structure inside another to represent hierarchical data.
The document states:
Here, struct Event contains struct Date as a member, allowing organized storage of related data
like event details.
4. Structure of Pointer in C - 2 Marks
A pointer to a structure in C stores the address of a structure variable. The document provides:
Members are accessed using the arrow operator (->): ptr->x = 10; modifies point1.x. This enables
efficient structure manipulation.
5. Local and Global Variables - 2 Marks
1.Local Variables: Declared inside a function, accessible only within it. Example from the
document:
p is destroyed when main() ends.
2. Global Variables: Declared outside functions, accessible everywhere. Example:
a can be used in test() and main().
6. Operators - 2 Marks
Dot Operator (. ): Accesses structure members directly. Example:
Arrow Operator (->): Accesses members via a pointer. Example:
