C Functions

Functions are a blocks of code that perform a specific task.
They help in modularizing the code, making it more readable, maintainable, and reusable.

Syntax
return_type function_name(parameter_type1 param1, parameter_type2 param2, ...){ // Function body // Code to perform the task // Return statement (if the function has a return type) return some_value; }
They are declared before they are used in the code.

#include <stdio.h>

// Function declaration
int add(int a, int b);

int main() {
    int result1,result2;

    // Function call
    result1 = add(3, 4);
    result2 = add(5, 9);
    
    // Output the result
    printf("Result1: %d\n", result1);
    printf("Result2: %d\n", result2);
    
    return 0;
}

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

You can declare a function many times.

Function Parameters

Parameters are values passed to the function when it's called.
Functions can have zero or more parameters.
Parameters are specified in the function declaration and definition.

Return Type

Functions may return a value using the return statement.
The return type is specified in the function declaration and definition.
If a function doesn't return a value, the return type is void.

Call a Function

To use a function, you call it in your code.
The function call includes the function name and actual arguments.
Using void function call a function

#include <stdio.h>

// Function declaration
void greet();

int main() {
    // Function call
    greet();

    return 0;
}

// Function definition
void greet() {
    printf("Hello, world!\n");
}

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