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5. Array in C
13. Boolean in C
18. Operators in C
33. Comments in C
38. Constants in C
41. Data Types in C
49. Double In C
58. For Loop in C
60. Functions in C
70. Identifiers in C
81. Linked list in C
83. Macros in C
86. Nested Loop in C
97. Pseudo-Code In C
100. Recursion in C
103. Square Root in C
104. Stack in C
106. Static function in C
107. Stdio.h in C
108. Storage Classes in C
109. strcat() in C
110. Strcmp in C
111. Strcpy in C
114. String Length in C
115. String Pointer in C
116. strlen() in C
117. Structures in C
119. Switch Case in C
120. C Ternary Operator
121. Tokens in C
125. Type Casting in C
126. Types of Error in C
127. Unary Operator in C
128. Use of C Language
In an age where the digital world is rapidly evolving, one language has continuously proven its relevance and resilience - C programming. As one of the most powerful and efficient languages, C programming provides a foundation that has shaped the digital realm. Designed for systems programming with an emphasis on low-level access to memory, a simple set of keywords, and a clean style, it has become a popular language for various software development.
In this tutorial, let’s go over some of the most important concepts and ideas in the world of C programming and walk you through some C programs for different themes that you can try out on your own!
In the constantly evolving landscape of software development, the importance of C programming remains paramount. Let’s navigate why C continues to be the most popular.
#include <stdio.h> |
As we delve into C programming, three fundamental concepts are crucial in constructing and managing our programs: Variables, Data Types, and Operators.
Variables in C are essentially the named memory locations used to store data within our program. Each variable in C has a specific type, which determines the size and layout of the variable's memory, the range of values that can be stored within that memory, and the set of operations that can be applied to the variable.
Data Types in C define the type of data that a variable can hold. The primary data types in C include int for integer values, float for floating-point values, double for double precision floating point values, char for character types, and _Bool for boolean types.
In C, operators are symbols that tell the compiler how to carry out particular logical or mathematical operations. The built-in operators in the C programming language include the following categories:
Declaring and initialising variables:
int a = 5; |
Primitive data types in C (int, float, char, etc.):
int a = 5;
float b = 3.14;
char c = 'A';
int age; // Integer data type |
Arithmetic, logical, and bit-wise operators in C:
// Arithmetic operators |
// Logical operators |
/_bitwise = a & b; |
In the journey of understanding C programming, one comes across a powerful set of tools known as control statements. These statements allow us to control the flow of execution in our programs, enabling more complex and dynamic behaviour beyond linear execution.
There are broadly two control statements in C: decision-making statements and looping statements.
Decision-making statements execute a particular block of code based on certain conditions. The primary decision-making statements in C are if, if-else, and switch.
Looping statements are used to repeatedly execute a code block until a certain condition is met. C provides three types of loops: for, while, and do-while.
Understanding arrays and pointers unlocks new possibilities in data manipulation and memory management, offering a more nuanced control over your programs. Let us explore these two concepts.
Arrays in C are data structures that can store fixed-size sequential elements of the same type. An array is used to store a collection of data, but it is often more useful to think of it as a collection of variables of the same type.
Pointers, on the other hand, are a bit more abstract. A pointer in C is a variable that stores the address of another variable. This allows for dynamic memory allocation, efficient handling of arrays and data structures, and enables the use of certain advanced programming techniques.
Declaring and initialising arrays:
int numbers[] = {1, 2, 3, 4, 5}; |
Array manipulation (sorting, searching, etc.):
// Sorting an array |
Pointers and memory allocation in C:
int x = 10; |
In the realm of C programming, functions and scope are two pivotal concepts that greatly enhance the structure and efficiency of your code. A function in C is a block of code that performs a specific task. By compartmentalising the code into functions, we can create reusable, easy-to-understand, and simple-to-manage modular pieces of code.
A function in C consists of a function declaration, definition, and calling:
In conjunction with functions, the concept of scope is also essential. Scope refers to the visibility and lifetime of variables in a program. In C, variables can have a local scope (visible within the function they are declared in) or global scope (visible throughout the program).
Understanding the scope helps maintain the integrity of the data and prevents potential conflicts in the program.
// Function declaration |
Structs (Structures) in C are used to group different types of data elements (variables) under a single name, offering a way of packaging related data together. For example, a student's record might be a struct containing fields for the name (char array), age (integer), and GPA (float).
Unions in C are similar to structs in that they allow us to store different types of data elements under a single name. However, while a struct allocates separate memory for each member, a union allocates a shared memory space that is used by all its member variables, one at a time.
Declaring and initialising structs and unions:
struct Point { |
Struct and union manipulation:
p1.x = 5; |
File Input/Output operations allow our programs to store information permanently and retrieve it later. This ability to read from and write to files enables programs to interact with data in a persistent and structured manner, greatly expanding their potential use cases.
In C, we perform file operations using a collection of functions provided by the C standard library. These functions allow us to open a file (fopen), close a file (fclose), read from a file (fread, fscanf, fgets), write to a file (fwrite, fprintf, fputs), and more.
For instance, you might write a program that maintains a log of its operations in a text file or a program that reads a large set of data from a binary file and processes it in some way.
Reading and writing to files:
FILE *file = fopen("example.txt", "w"); |
Creating, opening, and closing files in C:
```c |
Dynamic memory allocation allows programs to obtain memory dynamically during runtime. This ability to control memory allocation and deallocation enables the creation of intricate and flexible data structures and helps in optimising the performance and efficiency of C programs.
C offers several functions for dynamic memory management, including malloc(), calloc(), realloc(), and free(). These functions allow you to allocate memory blocks (malloc and calloc), adjust the size of allocated blocks (realloc), and free up memory when it is no longer needed (free).
For example, when working with data structures that grow and shrink during the execution of a program, such as linked lists, trees, and graphs, dynamic memory allocation becomes an invaluable tool.
Allocating and deallocating memory dynamically:
int *arr = (int *)malloc(5 * sizeof(int)); |
Using malloc(), calloc(), and realloc() functions:
// malloc: allocate memory without initialising it |
C Standard Library is a collection of header files, each containing a set of functions, macros, and types to be used in our programs. These predefined functions provide a wealth of pre-packaged functionality that can assist us in performing a range of common tasks, from mathematical operations and string manipulation to file handling and memory allocation.
Here are descriptions of some of the most commonly used standard library functions:
In this tutorial, we have covered the basics of C programming, including variables, data types, operators, control statements, arrays, pointers, functions, structs, unions, file I/O, dynamic memory allocation, and standard library functions. With this foundation, you are well-equipped to begin exploring more advanced topics and further develop your skills in C programming!
1. Is C still relevant in modern programming?
Yes, C remains relevant and widely used, particularly for system programming, embedded systems, and hardware programming.
2. What are the main differences between C and C++?
C++ is an extension of C that introduces object-oriented programming features, such as classes, objects, and inheritance. C++ also includes additional libraries and features, such as the Standard Template Library (STL).
3. Can I use C to develop web applications or mobile apps?
While it is possible to use C for web and mobile app development, other languages and frameworks (such as JavaScript, Python, or Java) are generally better suited for these tasks due to their higher-level abstractions and specialised libraries.
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