OutOfBoundsPanic.rs

fn main() {
	if std::env::args().count() != 2 {
		panic!("Pass exactly 1 argument: an index");
	}

	let index = match std::env::args().nth(1).unwrap().parse::<usize>() {
		Ok(i) => i,
		Err(_) => panic!("Pass a non-negative integer"),
	};

	let array: [i32; 4] = [0, 1, 2, 3];

	println!("index: {}", index);
	println!("value: {}", array[index]);
}