use std::collections::HashSet;

fn create_operator_set_recurse(
    operators_permutation_set: &mut HashSet<Vec<bool>>,
    operators: Vec<bool>,
) {
    operators_permutation_set.insert(operators.clone());
    if !operators.contains(&false) {
        return;
    }

    for i in 0..operators.len() {
        if operators[i] {
            continue;
        }
        let mut new_operators = operators.clone();
        new_operators[i] = true;
        create_operator_set_recurse(operators_permutation_set, new_operators);
    }
}

pub fn create_operator_set(num_of_operators: usize) -> HashSet<Vec<bool>> {
    let mut operator_sets: HashSet<Vec<bool>> = HashSet::new();
    create_operator_set_recurse(&mut operator_sets, vec![false; num_of_operators]);
    operator_sets
}