package main

import (
	"bufio"
	"fmt"
	"log"
	"os"
	"regexp"
	"strconv"
)

func getNum(s string) int {
	switch s {
	case "one":
		return 1
	case "two":
		return 2
	case "three":
		return 3
	case "four":
		return 4
	case "five":
		return 5
	case "six":
		return 6
	case "seven":
		return 7
	case "eight":
		return 8
	case "nine":
		return 9
	default:
		n, err := strconv.Atoi(s)
		if err != nil {
			return -1
		}
		return n
	}
}

func parseLine(line string) (int, int) {
	firstRe := regexp.MustCompile("([0-9]|one|two|three|four|five|six|seven|eight|nine)")
	lastRe := regexp.MustCompile(".*([0-9]|one|two|three|four|five|six|seven|eight|nine)")
	first := getNum(firstRe.FindStringSubmatch(line)[1])
	last := getNum(lastRe.FindStringSubmatch(line)[1])

	return first, last
}

func main() {
	fname := "input.txt"
	if len(os.Args) > 1 {
		fname = os.Args[1]
	}
	f, err := os.Open(fname)
	if err != nil {
		log.Fatal(err)
	}
	defer f.Close()

	sum := 0
	scanner := bufio.NewScanner(f)
	for scanner.Scan() {
		line := scanner.Text()
		first, last := parseLine(line)
		if os.Getenv("DEBUG") != "" {
			fmt.Println(10*first + last)
		}
		sum += 10*first + last
	}
	fmt.Println(sum)

	if err := scanner.Err(); err != nil {
		log.Fatal(err)
	}
}