Day 5 done

cmd/05/main.go

@@ -0,0 +1,17 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"aoc2024/internal/common"
+	"aoc2024/internal/day05"
+)
+
+func main() {
+	fmt.Println("Opening file...")
+	bytes := common.Must(os.ReadFile("/home/g3po/Projects/advent_of_code_2024/inputs/05.txt"))
+	result1, result2 := day05.Handle(bytes)
+	fmt.Println(result1)
+	fmt.Println(result2)
+}

internal/day05/handler.go

@@ -0,0 +1,79 @@
+package day05
+
+import (
+	"regexp"
+	"sort"
+	"strings"
+
+	"aoc2024/internal/common"
+)
+
+func Handle(input []byte) (int, int) {
+	inputs := separateInput(input)
+	rules := generateRules(inputs[0])
+	lines := strings.Split(strings.TrimSpace(inputs[1]), "\n")
+	result1, result2 := 0, 0
+
+	for _, line := range lines {
+		checkRules(line, rules, &result1, &result2)
+	}
+
+	return result1, result2
+}
+
+func separateInput(input []byte) []string {
+	re := regexp.MustCompile(`(?m)^\n*$`)
+	result := re.Split(string(input), -1)
+	result[0] = result[0][0 : len(result[0])-1]
+
+	return result
+}
+
+func generateRules(input string) map[int]map[int]struct{} {
+	re := regexp.MustCompile(`\d*`)
+	rules := map[int]map[int]struct{}{}
+	lines := strings.Split(input, "\n")
+
+	for _, line := range lines {
+		result := re.FindAllString(line, -1)
+		n1 := common.StrToInt(result[0])
+		n2 := common.StrToInt(result[1])
+
+		if _, ok := rules[n1]; !ok {
+			rules[n1] = map[int]struct{}{n2: {}}
+		} else {
+			rules[n1][n2] = struct{}{}
+		}
+
+	}
+	return rules
+}
+
+func checkRules(input string, rules map[int]map[int]struct{}, sum1, sum2 *int) {
+	numbersStr := strings.Split(input, ",")
+	number := make([]int, len(numbersStr))
+	for i, str := range numbersStr {
+		number[i] = common.StrToInt(str)
+	}
+
+	for i, n := range number {
+		for _, v := range number[:i+1] {
+			if _, ok := rules[n][v]; ok {
+				*sum2 += sortNumbers(number, rules)
+				return
+			}
+		}
+	}
+
+	*sum1 += number[len(number)/2]
+}
+
+func sortNumbers(n []int, rules map[int]map[int]struct{}) int {
+	sort.Slice(n, func(i, j int) bool {
+		_, ok := rules[n[i]][n[j]]
+		return ok
+	})
+
+	// fmt.Println(n)
+	return n[len(n)/2]
+}