day5 part2 completed

day5/main.go

@@ -14,7 +14,7 @@ func main() {
 	inputFile := os.Args[1]
 
 	part1, part2 := solution(inputFile)
-	fmt.Printf("(%s) Part 1: %d\n(%s) Part 2: %d\n:", inputFile, part1, inputFile, part2)
+	fmt.Printf("(%s) Part 1: %d\n(%s) Part 2: %d\n", inputFile, part1, inputFile, part2)
 }
 
 type Rule struct {
@@ -86,12 +86,63 @@ func solution(inputFile string) (int, int) {
 
 		if validUpdate {
 			validSum += updatePages[len(updatePages)/2]
+		} else {
+			invalidSum += reorderedMid(updatePages, rules)
 		}
 	}
-
 	return validSum, invalidSum
 }
 
+func reorderedMid(pages []int, rules []Rule) int {
+	corrected := false
+	for !corrected {
+		for i := 0; i < len(pages); i++ {
+			for j := 1; j < len(pages); j++ {
+				if i == j {
+					continue
+				}
+				if i < j {
+					valid := isValid(rules, pages[i], pages[j])
+					if !valid {
+						pages[i], pages[j] = pages[j], pages[i]
+					}
+				} else {
+					valid := isValid(rules, pages[j], pages[i])
+					if !valid {
+						pages[i], pages[j] = pages[j], pages[i]
+					}
+				}
+			}
+		}
+
+		corrected = wasCorrected(pages, rules)
+	}
+	fmt.Printf("Corrected %v\n", pages)
+	return pages[len(pages)/2]
+}
+
+func wasCorrected(pages []int, rules []Rule) bool {
+	for i := 0; i < len(pages); i++ {
+		for j := 1; j < len(pages); j++ {
+			if i == j {
+				continue
+			}
+			if i < j {
+				valid := isValid(rules, pages[i], pages[j])
+				if !valid {
+					return false
+				}
+			} else {
+				valid := isValid(rules, pages[j], pages[i])
+				if !valid {
+					return false
+				}
+			}
+		}
+	}
+	return true
+}
+
 func isValid(rules []Rule, left, right int) bool {
 	for _, rule := range rules {
 		if rule.Left == right && rule.Right == left {