adventofcode2024/day_03/src/main.rs

// https://adventofcode.com/2024/day/3
//
// Run command: cargo run ./input.txt

mod op;
mod parser;
mod tokenizer;

use crate::op::Ops;
use crate::parser::parse_tokens;
use crate::tokenizer::{Token, tokenize};

use core::panic;
use std::env;
use std::error::Error;
use std::fs::File;
use std::io::{BufReader, prelude::*};

fn main() -> Result<(), Box<dyn Error>> {
    // Handle command input
    let args: Vec<String> = env::args().collect();
    if args.len() != 2 {
        panic!(
            "{} must be run with a single argument of files name!",
            &args[0]
        )
    }
    let input_file_string = &args[1];

    let input_buffer = BufReader::new(File::open(input_file_string)?);

    let mut tokens: Vec<Token> = Vec::new();
    for line in input_buffer.lines() {
        tokens.append(&mut tokenize(line? + "\n"));
    }
    //println!("{:?}", tokens);

    let muls = parse_tokens(&tokens);
    //println!("{:?}", muls);

    let mut accumulator_part1: i64 = 0;
    let mut accumulator_part2: i64 = 0;
    let mut enabled: bool = true;
    for op in muls {
        match op {
            Ops::Mul(mul_op) => {
                let value = mul_op.multiple::<i64>()?;
                accumulator_part1 += value;
                if enabled {
                    accumulator_part2 += value;
                }
            }
            Ops::Do(_) => enabled = true,
            Ops::Dont(_) => enabled = false,
        }
    }

    println!("Answer part 1: {}", accumulator_part1);
    println!("Answer part 2: {}", accumulator_part2);

    Ok(())
}