I also used Go - my solution for part 1 was essentially identical to yours. I went a different route for part 2 that I think ended up being simpler though.
I just prepended do() and don't() to the original regex with a |, that way it captured all 3 in order and I just looped through all the matches once and toggled the isEnabled flag accordingly.
Always interesting to see how other people tackle the same problem!
Part 2 Code
func part2() {
filePath := "input.txt"
file, _ := os.Open(filePath)
defer file.Close()
pattern := regexp.MustCompile(`do\(\)|don't\(\)|mul\((\d{1,3}),(\d{1,3})\)`)
productSum := 0
isEnabled := true
scanner := bufio.NewScanner(file)
for scanner.Scan() {
line := scanner.Text()
matches := pattern.FindAllStringSubmatch(line, -1)
for _, match := range matches {
if match[0] == "do()" {
isEnabled = true
} else if match[0] == "don't()" {
isEnabled = false
} else if isEnabled && len(match) == 3 {
n, _ := strconv.Atoi(match[1])
m, _ := strconv.Atoi(match[2])
productSum += n * m
}
}
}
fmt.Println("Total: ", productSum)
}
I also used Go - my solution for part 1 was essentially identical to yours. I went a different route for part 2 that I think ended up being simpler though.
I just prepended
do()anddon't()to the original regex with a|, that way it captured all 3 in order and I just looped through all the matches once and toggled theisEnabledflag accordingly.Always interesting to see how other people tackle the same problem!
Part 2 Code