use std::fmt::{self, Display};
struct Wrap<T>(T);
impl<T: Display> Display for Wrap<Vec<T>> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
for (ix, r) in self.0.iter().enumerate() {
if ix > 0 {
write!(f, " ")?;
}
r.fmt(f)?;
}
Ok(())
}
}
#[argio::argio(multicase = "0-based index = {i}: ", output = Wrap)]
fn main(n: usize) -> Vec<usize> {
(0..n).map(|i| i * 2).collect()
}