Main (Entry Point)

C

int main(int argc, const char **argv)
{
	// Code Here

	return 0; // 0 (zero) means successful end of program
}

int main(int argc, const char *argv[])
{
	// Code Here

	return 0;
}

#include <stdlib.h> // For exit(), EXIT_SUCCESS, EXIT_FAILURE

int main(void)
{
	// Code Here

	// In some codes, instead of "return 0", you might find One of the following:
	return exit(0);
	return EXIT_SUCCESS;
	return exit(EXIT_SUCCESS);
}

More Info:

• https://www.geeksforgeeks.org/command-line-arguments-in-c-cpp/
• https://stackoverflow.com/questions/13667364/exit-failure-vs-exit1

C++

int main(int argc, const char **argv)
{
	// Code Here

	return 0; // 0 (zero) means successful end of program
}

int main(int argc, const char *argv[])
{
	// Code Here

	return 0;
}

#include <cstdlib> // For exit(), EXIT_SUCCESS, EXIT_FAILURE

int main(void)
{
	// Code Here

	// In some codes, instead of "return 0", you might find One of the following:
	return exit(0);
	return EXIT_SUCCESS;
	return exit(EXIT_SUCCESS);
}

More Info:

• https://www.geeksforgeeks.org/command-line-arguments-in-c-cpp/
• https://stackoverflow.com/questions/13667364/exit-failure-vs-exit1

C#

public class MyClassName
{
	public static void Main(string[] args)
	{
		// Code Here
	}
}

More Info:

• https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/main-and-command-args/
• https://www.geeksforgeeks.org/main-method-in-c-sharp/

Java

public static void main(String[] args)
{
	// Code Here
}

Rust

fn main() {
	// Code Here
}

// Args Example
fn main() {
	let args: Vec<String> = std::env::args().collect();

	for arg in args {
		println!("{}", arg);
	}
}

Go

package main

import "fmt"

func main() {
	// Code Here
	fmt.Println("Hello World")
}

// Args Example
package main

import (
	"fmt"
	"os"
)

func main() {
	for _, arg := range os.Args {
		fmt.Println(arg)
	}
}

Javascript

// You dont need a main function. The Code runs top to bottom
// But, if you want to be organized:

function main() {
	// Code Here
}

main();

// Self Invoking Function
(function main() {
	// Code Here
})();

class Main {
	static Run() {
	// Code Here
	}
}

Main.Run();

// Args Example (Node)
const args = process.argv.slice(2);

for (const arg of args) {
	console.log(arg);
}

Typescript

// You dont need a main function. The Code runs top to bottom
// But, if you want to be organized:

function main(): void {
	// Code Here
}

main();

class Main {
	public static Run(): void {
		// Code Here
	}
}

Main.Run();

// Args Example (Node)
const args: string[] = process.argv.slice(2);

for (const arg of args) {
	console.log(arg);
}

Python

# You dont need a main function. The Code runs top to bottom
# But, if you want to be organized:

def main():
	# Code Here

main()

# There are no "{ }", you need to use ":" and indentation
# You can have either spaces or tabs but not both mixed

def main():
	# Code Here

# Conditional to check If you are running the source file as
# the main program entry point (Instead of importing it from another file)

if (__name__ == "__main__"):
	main()

class Main:
	@staticmethod
	def run():
		# Code Here

if (__name__ == "__main__"):
	Main.run()

# Args Example
import sys

for arg in sys.argv[1:]:
	print(arg)