Functions are blocks of code that perform specific tasks. They need to be declared before using them.
// Function declaration
int add_numbers(int a, int b);

// Function definition
int add_numbers(int a, int b) {
    return a + b;
}

break is used to exit the loop prematurely, while continue is used to skip the current iteration and proceed to the next.

for (int i = 1; i <= 10; i++) {
    if (i == 5) {
        break; // Exit the loop when i is 5
    }
    printf("%d ", i);
}
// Output: 1 2 3 4

for (int i = 1; i <= 5; i++) {
    if (i == 3) {
        continue; // Skip the iteration when i is 3
    }
    printf("%d ", i);
}
// Output: 1 2 4 5

Loops allow you to execute a block of code repeatedly.

// Using a for loop to print numbers from 1 to 5
for (int i = 1; i <= 5; i++) {
    printf("%d ", i);
}
printf("\n");

// Using a while loop to calculate the sum of numbers from 1 to 10
int sum = 0, i = 1;
while (i <= 10) {
    sum += i;
    i++;
}
printf("Sum: %d\n", sum);

// Using a do-while loop to print numbers from 1 to 5
int num = 1;
do {
    printf("%d ", num);
    num++;
} while (num <= 5);
printf("\n");

int day = 3;
switch (day) {
    case 1:
        printf("Monday\n");
        break;
    case 2:
        printf("Tuesday\n");
        break;
    // ...
    default:
        printf("Invalid day\n");
}

Conditional statements allow you to execute different code blocks based on certain conditions.

int num = 10;
if (num > 0) {
    printf("Positive\n");
} else if (num < 0) {
    printf("Negative\n");
} else {
    printf("Zero\n");
}

`printf()` is used to display output to the console, and scanf() is used to read input from the user.

int age;
printf("Enter your age: ");
scanf("%d", &age);
printf("Your age is %d\n", age);

C supports various operators for performing arithmetic, comparison, logical, and bitwise operations.

int x = 10, y = 5;
int sum = x + y; // Arithmetic operator (+)
int is_equal = (x == y); // Comparison operator (==)
int is_true = (x && y); // Logical AND operator (&&)

Constants are fixed values that cannot be modified during the program's execution. In C, you can use literals to represent constants.
#define PI 3.14159  // Declaring a symbolic constant using a #define directive
const int MAX_SIZE = 100;  // Declaring a constant variable using the const keyword

Data Types and Variables:
In C, you need to declare variables with their data types before using them. Common data types include int, float, char, double, etc.
int age;        // Declaration of an integer variable
float pi = 3.14;  // Declaration and initialization of a float variable
char letter = 'A'; // Declaration and initialization of a char variable

The "Hello, World!" program is a simple introductory program that prints the text "Hello, World!" to the console. Here's how you can do it:

#include <stdio.h>

int main() {
    printf("Hello, World!\n");
    return 0;
}