feat(golang): initialize shared framework and refactor day 1

Created 'aoc-go-common' module for shared Go utilities and runner. Migrated 2024 Day 1 to use this new framework.

Author: markkovari

2024/golang/cmd/day01.go

@@ -0,0 +1,56 @@
+package main
+
+import (
+	"fmt"
+	"math"
+	"sort"
+	"strconv"
+	"strings"
+
+	"github.com/markkovari/advent_of_code/aoc-go-common"
+)
+
+type Day01 struct{}
+
+func (d Day01) Part1(input string) string {
+	left, right := parse(input)
+	sort.Slice(left, func(i, j int) bool { return left[i] < left[j] })
+	sort.Slice(right, func(i, j int) bool { return right[i] < right[j] })
+
+	var sum int64
+	for i := range left {
+		sum += int64(math.Abs(float64(right[i] - left[i])))
+	}
+	return fmt.Sprintf("%d", sum)
+}
+
+func (d Day01) Part2(input string) string {
+	left, right := parse(input)
+	similarity := make(map[int64]int)
+	for _, n := range right {
+		similarity[n]++
+	}
+
+	var sum int64
+	for _, n := range left {
+		sum += n * int64(similarity[n])
+	}
+	return fmt.Sprintf("%d", sum)
+}
+
+func parse(input string) ([]int64, []int64) {
+	left, right := make([]int64, 0), make([]int64, 0)
+	for _, line := range strings.Split(input, "\n") {
+		if line == "" { continue }
+		parts := strings.Fields(line)
+		l, _ := strconv.ParseInt(parts[0], 10, 64)
+		r, _ := strconv.ParseInt(parts[1], 10, 64)
+		left = append(left, l)
+		right = append(right, r)
+	}
+	return left, right
+}
+
+func main() {
+	common.Run(2024, 1, Day01{})
+}