adventofcode2024/day_04/src/main.rs

//https://adventofcode.com/2024/day/4
//
// Run command: cargo run ./input.txt

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

#[derive(Debug)]
struct Crossword {
    data: Vec<Vec<char>>,
    width: usize,
    height: usize,
}

impl Crossword {
    fn new(file: File) -> Result<Crossword, Box<dyn Error>> {
        let mut input_buffer = BufReader::new(file);

        let mut data: Vec<Vec<char>> = Vec::new();

        let mut first_line = String::new();
        input_buffer.read_line(&mut first_line)?;
        let first_line = first_line.trim_end().to_owned();
        let width = first_line.len();
        for line in input_buffer.lines() {
            let line = line?;
            if line.len() != width {
                println!("{}", line);
                Err("Line length of input are not consistent")?;
            }
            data.push(line.chars().collect());
        }
        let height = data.len();

        Ok(Crossword {
            data,
            width,
            height,
        })
    }
}

impl Display for Crossword {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        for row in &self.data {
            let row = String::from_iter(row.iter());
            writeln!(f, "{}", row)?;
        }
        Ok(())
    }
}

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 crossword = Crossword::new(File::open(input_file_string)?)?;

    println!("{}", crossword);

    Ok(())
}