src/bin/day_1.rs


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extern crate advent_of_code_2018;
use advent_of_code_2018::*;

use std::error::Error;
use std::path::PathBuf;

use std::collections::HashSet;

// cargo watch -cs "cargo run --bin day_1"

fn main() -> Result<(), Box<Error>> {
    let input = read_file(&PathBuf::from("inputs/1.txt"))?;
    let input_ints: Vec<i32> = input.iter().map(|str| str.parse::<i32>().unwrap()).collect();

    println!("Input: {:?}", input_ints);

    let sum: i32 = input_ints.iter().sum();
    println!("Sum: {}", sum);

    let mut seen = HashSet::new();
    let mut acc = 0;
    let mut repeat_found = false;
    while !repeat_found {
        for i in &input_ints {
            if seen.contains(&acc) {
                repeat_found = true;
                break;
            } else {
                seen.insert(acc);
            }
            acc += i;
        }
    }
    println!("First repeat: {}", acc);

    Ok(())
}