What are Variadic functions?

Variadic functions are functions that accept a variable number of arguments. This allows you to pass any number of parameters when calling the function.

📌 In JavaScript:

JavaScript supports variadic functions using the rest parameter (...) or the special object arguments.

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1. Using Rest Parameter (...)

function sum(...numbers) {
    return numbers.reduce((total, num) => total + num, 0);
}

console.log(sum(1, 2, 3));      // Output: 6
console.log(sum(5, 10, 15, 20)); // Output: 50

• ...numbers collects all arguments into an array.

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2. Using arguments Object (older method)

function multiply() {
    let result = 1;
    for (let i = 0; i < arguments.length; i++) {
        result *= arguments[i];
    }
    return result;
}

console.log(multiply(2, 3, 4)); // Output: 24

• arguments is array-like but not a true array.

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📌 In Python:

Python uses *args for positional arguments and **kwargs for keyword arguments.

Example:

def greet(*names):
    for name in names:
        print(f"Hello, {name}!")

greet("Alice", "Bob", "Charlie")
# Output:
# Hello, Alice!
# Hello, Bob!
# Hello, Charlie!

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📌 In C/C++:

C/C++ uses stdarg.h for variadic functions.

Example:

#include <stdio.h>
#include <stdarg.h>

void printNumbers(int count, ...) {
    va_list args;
    va_start(args, count);

    for (int i = 0; i < count; i++) {
        printf("%d ", va_arg(args, int));
    }

    va_end(args);
    printf("\n");
}

int main() {
    printNumbers(3, 10, 20, 30);  // Output: 10 20 30
    return 0;
}

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✅ Summary:

• Variadic functions allow flexibility by accepting multiple arguments.
• In modern JavaScript, the rest parameter (...args) is the preferred method.