let (a, b) = ("Pl", "ng");

	let (prefix, suffix, mut out) = ("Pl", "ng", String::with_capacity(15));

	let c =
		[(3, "i"), (5, "a"), (7, "o")]
			.iter()
			.fold(String::with_capacity(15), |mut d, (e, f)| {
				if n % e == 0 {
					d.push_str(a);
					d.push_str(f);
					d.push_str(b);
				}
				d
			});

	[(3, "i"), (5, "a"), (7, "o")]
		.iter()
		.for_each(|(factor, vowel)| {
			if n % factor == 0 {
				out.push_str(prefix);
				out.push_str(vowel);
				out.push_str(suffix)
			}
		});

	if c.is_empty() {

	if out.is_empty() {

		c

		out