Discussion on: Advent of Code 2020 Solution Megathread - Day 8: Handheld Halting

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Rust! I am doing WAY too much object copying. I think I could get the same results by passing vector of references around. But, wanted to not think too much :)
use std::collections::HashSet;
use std::mem::swap;

#[derive(Debug, PartialOrd, PartialEq, Clone)]
enum ActionType {
    Acc,
    Jmp,
    Nop,
}

#[derive(Debug, PartialOrd, PartialEq, Clone)]
struct Action {
    num: i32,
    action: ActionType,
}

impl Action {
    fn run(&self, pos: &i32, accumulator: &i32) -> (i32, i32) {
        match self.action {
            ActionType::Acc => (pos + 1, accumulator + self.num),
            ActionType::Jmp => (pos + self.num, accumulator.clone()),
            ActionType::Nop => (pos + 1, accumulator.clone()),
        }
    }
}

fn run_actions(input: &[Action]) -> (i32, bool, Vec<usize>) {
    let mut actions_taken = HashSet::new();
    let mut action_order = vec![];
    let mut curr_action: usize = 0;
    let mut acc: i32 = 0;
    loop {
        let action = match input.get(curr_action) {
            Some(a) => a,
            None => return (acc, true, action_order),
        };
        let (new_action, new_acc) = action.run(&(curr_action as i32), &acc);
        action_order.push(new_action as usize);
        if actions_taken.contains(&new_action) {
            return (acc, false, action_order);
        }
        curr_action = new_action as usize;
        acc = new_acc;
        actions_taken.insert(new_action);
    }
}

#[aoc(day8, part1)]
fn last_value_before_rerun(input: &Vec<Action>) -> i32 {
    run_actions(input.as_slice()).0
}

#[aoc(day8, part2)]
fn fix_program(input: &Vec<Action>) -> i32 {
    let (_, _, mut action_order) = run_actions(input.as_slice());
    action_order.reverse();
    for action in action_order
        .iter()
        .filter(|a| input.get(**a).unwrap().action != ActionType::Acc)
    {
        let to_swap: &Action = input.get(*action).unwrap();
        let swapped = match to_swap.action {
            ActionType::Nop => Action {
                num: to_swap.num,
                action: ActionType::Jmp,
            },
            ActionType::Jmp => Action {
                num: to_swap.num,
                action: ActionType::Nop,
            },
            _ => unreachable!(),
        };
        let (acc, finished, _) = run_actions(
            [&input[0..*action], &[swapped], &input[*action + 1..]]
                .concat()
                .as_slice(),
        );
        if finished {
            return acc;
        }
    }
    0
}