use std::fs::File;
use std::io::{self, prelude::*, BufReader};

fn process_line(line: String) -> u32 {
    let mut first_digit: u32 = 0;
    let mut last_digit: u32 = 0;
    for i in line.chars() {
        if i.is_numeric() {
            first_digit = i as u32 - '0' as u32;
            break;
        }
    }
    for i in line.chars().rev() {
        if i.is_numeric() {
            last_digit = i as u32 - '0' as u32;
            break;
        }
    }
    println!("{}{}", first_digit, last_digit);
    return first_digit*10+last_digit;
}

fn main() -> io::Result<()>  {
    let mut sum: u32 = 0;
    let file = File::open("../input.txt")?;
    let reader = BufReader::new(file);
    for line in reader.lines() {
        sum = process_line(line?) + sum;
    }
    println!("{}", sum);

    Ok(())
}