adventofcode2023/day1/part2.go

86 lines
1.4 KiB
Go

package main
import (
"errors"
"fmt"
"io"
"log"
"os"
"regexp"
"strconv"
"strings"
)
func readInput() string {
stdin, err := io.ReadAll(os.Stdin)
if err != nil {
panic(err)
}
str := string(stdin)
return str
}
func parseDigit(input string) (string, error) {
digits := map[string]string{
"one": "1",
"two": "2",
"three": "3",
"four": "4",
"five": "5",
"six": "6",
"seven": "7",
"eight": "8",
"nine": "9",
"1": "1",
"2": "2",
"3": "3",
"4": "4",
"5": "5",
"6": "6",
"7": "7",
"8": "8",
"9": "9",
}
i, ok := digits[input]
if ok == false {
return "", errors.New("No spelled digit")
}
return i, nil
}
func addDStrings(input1 string, input2 string) string {
num1, err := parseDigit(input1)
if err != nil {
num1 = input1
}
num2, err := parseDigit(input2)
if err != nil {
num2 = input2
}
num_str := num1 + num2
return num_str
}
func main() {
lines := strings.Split(readInput(), "\n")
re := regexp.MustCompile(`(one|two|three|four|five|six|seven|eight|nine|\d)`)
var answer int
for _, l := range lines {
matches := re.FindAllString(l, -1)
matches_len := len(matches)
if matches_len == 0 {
continue
}
first := matches[0]
last := matches[matches_len-1]
num_str := addDStrings(first, last)
num, err := strconv.Atoi(num_str)
if err != nil {
log.Fatalln(err)
}
answer = answer + num
fmt.Println(l, first, last, num)
}
fmt.Println(answer)
}