use std::error::Error;
use std::fs::File;
use std::io::BufReader;
use std::io::prelude::*;

fn main() -> std::io::Result<()> {
    let file = match File::open("input") {
        // The `description` method of `io::Error` returns a string that describes the error
        Err(why) => panic!("couldn't open input: {}", Error::description(&why)),
        Ok(file) => file,
    };

    let reader = BufReader::new(file);
    let lines = reader.lines();

    let mut total: i128 = 0;

    for result in lines {
        let l = result.unwrap();
        let offset:i128 = i128::from_str_radix(&l, 10).unwrap();

        println!("{} => {}", l, offset);

        total = total + offset;
    }

    println!("{}", total);

    Ok(())
}