C Programming Basics are the foundation for anyone looking to start coding. This guide will walk you through key concepts like variables, data types, operators, and input/output functions to help you build a solid programming base.

Variables and Data Types

In C, a variable is a named storage location that holds a value. The data type determines the size and type of value it can store.

Primary Data Types:

int:

Stores integer values (e.g., 123, -456)

int myVar = 100;

char:

Stores single characters (e.g., ‘a’, ‘B’).

char myChar = 'A';

float:

Stores floating-point numbers (e.g., 3.14f).

float pi = 3.1415926535f;

double:

Stores double-precision floating-point numbers.

double largePi = 3.14159265358979323862;

Modifiers:

unsigned:

Allows only non-negative values.

unsigned int uVar = 100; // Cannot be negative

signed: Explicitly allows negative values (default for int and char).

const:

Makes the variable’s value constant.

const int MAX = 100; // Value cannot change

Operators

C provides various operators to perform operations on variables and constants.

Arithmetic Operators:

+ (Addition), - (Subtraction), * (Multiplication), / (Division), % (Modulus).

int sum = 10 + 20; // sum is 30

Comparison Operators:

== (Equal to), != (Not equal to), > (Greater than), < (Less than), >= (Greater than or equal to), <= (Less than or equal to).

if (a == b) { /* code */ }

Logical Operators:

&& (Logical AND), || (Logical OR), ! (Logical NOT).

&& (Logical AND), || (Logical OR), ! (Logical NOT).

Assignment Operators:

= (Assign), += (Add and assign), -= (Subtract and assign), *= (Multiply and assign), /= (Divide and assign).

int x = 5;
x += 10; // x is now 15

Bitwise Operators:

& (AND), | (OR), ^ (XOR), ~ (NOT), << (Left shift), >> (Right shift).

unsigned char a = 5; // binary 0101
unsigned char b = 3; // binary 0011
unsigned char c = a & b; // binary 0001, which is 1

Ternary Operator (Conditional):

Syntax: condition ? result_if_true : result_if_false

int max = (a > b) ? a : b;

Input/Output

C uses standard library functions for input and output.

Output with printf():

• Prints formatted output to the screen.
• Format specifiers: %d (integer), %c (character), %f (float), %lf (double), %s (string).

printf("Hello, World!\n"); // Output: Hello, World!
int num = 10;
printf("Number is %d\n", num); // Output: Number is 10

Input with scanf():

• Reads formatted input from the keyboard.
• Use address-of operator & for variables except strings.

int age;
printf("Enter your age: ");
scanf("%d", &age); // Note the &

By understanding these C programming basics, you’ll be better prepared to tackle more complex coding challenges. Keep practicing, explore new concepts, and soon you’ll be writing efficient C programs with ease.