// Copyright 2023 Christian Ulrich
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
// usage: ./part2 < input

use std::io;

pub struct CalibrationValues {
    inner: Vec<u32>,
}

impl CalibrationValues {
    pub fn from_stdin(tokens: &[(&str, u32)]) -> Result<Self, &'static str> {
        let mut values = vec![];
        for line in io::stdin().lines() {
            let line = line.unwrap();
            let mut matches = Vec::new();
            for (token, value) in tokens.iter() {
                match line.find(token) {
                    Some(pos) => matches.push((pos, value)),
                    None => (),
                }
                match line.rfind(token) {
                    Some(pos) => matches.push((pos, value)),
                    None => (),
                }
            }
            if matches.len() > 0 {
                matches.sort_by_key(|(pos, _)| *pos);
                let first = matches.first().unwrap().1;
                let last = matches.last().unwrap().1;
                values.push(first * 10 + last);
            }
        }
        Ok(Self { inner: values })
    }

    pub fn iter(&mut self) -> std::slice::Iter<'_, u32> {
        self.inner.iter()
    }
}

fn main() -> Result<(), &'static str> {
    let tokens = [
        ("1", 1),
        ("2", 2),
        ("3", 3),
        ("4", 4),
        ("5", 5),
        ("6", 6),
        ("7", 7),
        ("8", 8),
        ("9", 9),
        ("one", 1),
        ("two", 2),
        ("three", 3),
        ("four", 4),
        ("five", 5),
        ("six", 6),
        ("seven", 7),
        ("eight", 8),
        ("nine", 9),
    ];
    let mut values = CalibrationValues::from_stdin(&tokens[..])?;
    println!("{}", values.iter().sum::<u32>());
    Ok(())
}