AoC-Day1.go

aoc-day1.go

package main

import (
    "os"
	"encoding/csv"
	"regexp"
	"fmt"
	"strings"
	"strconv"
)

func check(e error) {
    if e != nil {
        panic(e)
    }
}

func main() {
file, err := os.Open("input.txt")
    check(err)
    defer file.Close() 
    reader := csv.NewReader(file) 
    records, err := reader.ReadAll() 
	check(err)

	re := regexp.MustCompile(`\d`)
	
	var sum int64 = 0

	for _, eachline := range records { 
		digits := eachline[0]
		words := []string{"zero", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine"}
		mod_words := []string{"ze0ro", "on1ne", "tw2wo", "thr3ree", "fou4ur", "fiv5ve", "si6ix", "sev7ven", "eig8ght", "ni9ine"}

		for i:=0;i<=9; i++{
			digits = strings.ReplaceAll(digits,words[i],mod_words[i])
		}
		
		digit_slice := re.FindAllStringSubmatch(digits,-1)
		//final calibration number
		calibration_string := digit_slice[0][0] + digit_slice[len(digit_slice)-1][0]
		
		calibration_int, err := strconv.ParseInt(calibration_string,10,16)
		check(err)

		sum += calibration_int
	}
	fmt.Println(sum)
}