class Item {
  n: Int
}

class Bag {
  items: multi Item
}

fn swap(mut a: Item, mut b: Item) -> Int {
  return 0
}

fn bump(mut a: Item, b: Item) -> Int {
  return 0
}

fn look(a: Item, b: Item) -> Int {
  return 0
}

fn shuffle(mut bag: Bag, i: Int, j: Int) -> Int {
  let dyn_pair = swap(bag.items[i], bag.items[j])
  let const_pair = swap(bag.items[0], bag.items[1])
  let mixed_pair = bump(bag.items[i], bag.items[j])
  let shared_pair = look(bag.items[i], bag.items[j])
  return dyn_pair + const_pair + mixed_pair + shared_pair
}

fn shuffle_via_aliases(mut bag: Bag, i: Int, k: Int) -> Int {
  let r = bag.items[i]
  let s = bag.items[k]
  return swap(r, s)
}