Function subsets 

pub fn subsets<T: Clone>(items: &[T]) -> Vec<Vec<T>>

Barcha qism to’plamlar (power set) — 2ⁿ ta.

G’oya: har bir element uchun ikkita qaror — “olaman” yoki “olmayman”.

Misol

use rust_algorithms::other::backtracking::subsets;

let s = subsets(&[1, 2, 3]);
assert_eq!(s.len(), 8);
assert!(s.contains(&vec![]));
assert!(s.contains(&vec![1, 3]));