feat(2024): refactor day 3

Refactored Day 3 of 2024 to use the common framework. Successfully migrated solution and integrated it into the runner.

Author: markkovari

2024/golang/cmd/day03.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"fmt"
+	"regexp"
+	"strconv"
+
+	"github.com/markkovari/advent_of_code/aoc-go-common"
+)
+
+type Day03 struct{}
+
+func (d Day03) Part1(input string) string {
+	pattern := regexp.MustCompile(`mul\((\d+),(\d+)\)`)
+	matches := pattern.FindAllStringSubmatch(input, -1)
+	var sum int64
+	for _, m := range matches {
+		sum += toInt(m[1]) * toInt(m[2])
+	}
+	return fmt.Sprintf("%d", sum)
+}
+
+func (d Day03) Part2(input string) string {
+	pattern := regexp.MustCompile(`mul\((\d+),(\d+)\)|do\(\)|don't\(\)`)
+	matches := pattern.FindAllStringSubmatch(input, -1)
+	var sum int64
+	enabled := true
+	for _, m := range matches {
+		switch m[0] {
+		case "do()":
+			enabled = true
+		case "don't()":
+			enabled = false
+		default:
+			if enabled {
+				sum += toInt(m[1]) * toInt(m[2])
+			}
+		}
+	}
+	return fmt.Sprintf("%d", sum)
+}
+
+func toInt(s string) int64 {
+	val, _ := strconv.ParseInt(s, 10, 64)
+	return val
+}
+
+func main() {
+	common.Run(2024, 3, Day03{})
+}