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extern crate advent_of_code_2018;
use advent_of_code_2018::*;

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

extern crate im_rc;
use im_rc::HashMap;

// cargo watch -cs "cargo run --release --bin day_2"

fn main() -> Result<(), Box<Error>> {
    let input = read_file(&PathBuf::from("inputs/2.txt"))?;

    println!("Input: {:?}", input);
    
    let (twice, thrice) = input.iter().fold((0,0), |(twice, thrice), next| {
        let occurances = next.chars().fold(HashMap::new(), |occurances, c| {
            let counter = occurances.get(&c).cloned().unwrap_or(0);
            occurances.update(c, counter + 1)
        });
        let has_twice = occurances.values().any(|count| *count == 2);
        let has_thrice = occurances.values().any(|count| *count == 3);

        (
            twice + if has_twice { 1 } else { 0 },
            thrice + if has_thrice { 1 } else { 0 },
        )
    });
    
    println!("Twice: {}", twice);
    println!("Thrice: {}", thrice);
    
    let checksum = twice * thrice;
    println!("Checksum: {}", checksum);

    for i in &input {
        for j in &input {
            let diff = i.chars().zip(j.chars()).fold(0, |diff, (x, y)| {
                if x != y {
                    diff + 1
                } else {
                    diff
                }
            });
            if diff == 1 {
                println!("Diff of 1: {} + {}", i, j);
            }
        }
    }
    
    Ok(())
}