day19, part2, finally

.gitignore

@@ -1,2 +1,4 @@
 /.direnv/
 /.go
+example
+/day19/input

day18/notes.org

@@ -43,3 +43,9 @@ day18 result: 952407566854
 *** and with separate done channel from the summing goroutine
 952408144115
 **** YES
+** and
+2023/12/18 23:35:31 border is 195341588; inside is 148441957805559
+2023/12/18 23:35:31
+
+day18 result: 148442153147147
+* i should have used a formula. maybe then it would taken less than 4 hours

day19/example1

@@ -0,0 +1,5 @@
+in{x<4000:R,m<4000:R,A}
+px{a<4000:R,A}
+qqz{s>2770:R,m<1801:A,R}
+
+{x=787,m=2655,a=1222,s=2876}

day19/intervals.go

@@ -0,0 +1,57 @@
+package day19
+
+import (
+	"sort"
+)
+
+func merge(intervals [][]int) [][]int {
+    const start, end = 0, 1
+
+    var merged [][]int
+
+    if len(intervals) > 1 {
+        sort.Slice(intervals, func(i, j int) bool {
+            return intervals[i][start] < intervals[j][start]
+        })
+    }
+
+    for _, interval := range intervals {
+        last := len(merged) - 1
+        if last < 0 || interval[start] > merged[last][end] {
+            merged = append(merged,
+                []int{start: interval[start], end: interval[end]},
+            )
+        } else if interval[end] > merged[last][end] {
+            merged[last][end] = interval[end]
+        }
+    }
+
+    return merged[:len(merged):len(merged)]
+}
+
+func applyLessThan(intervals [][]int, n int) [][]int {
+	var lessers [][]int
+	for _, interval := range intervals {
+		from := interval[0]
+		if from >= n {
+			continue
+		}
+		lessers = append(lessers, []int{from, n-1})
+	}
+
+	return lessers
+}
+
+func applyMoreThan(intervals [][]int, n int) [][]int {
+	var greaters [][]int
+	for _, interval := range intervals {
+		to := interval[1]
+		if to <= n {
+			continue
+		}
+		greaters = append(greaters, []int{n+1, to})
+	}
+	// log.Printf(">>>> in applyMoreThan %d to %+v ; result %+v", n, intervals, greaters)
+
+	return greaters
+}

day19/notes.org

@@ -0,0 +1,47 @@
+#+title: Notes
+* testing things
+
+	testSorter := day19.ReadSorterLine("qqz{s>2770:qs,m<1801:hdj,R}")
+	log.Printf("my test sorter is %+v", testSorter)
+
+	testOperation := day19.ReadOperationLine("s>2770:qs")
+	log.Println(testOperation)
+** testing simplification
+	 lnx{m>1548:A,A}
+	 qqz{s>2770:qs,m<1801:hdj,R}
+	 kt{m>2215:R,x>3386:A,x<3107:R,R}
+
+	testSorter := day19.ReadSorterLine("kt{m>2215:R,x>3386:A,x<3107:R,R}")
+	log.Printf("my test sorter is %+v", testSorter)
+
+	simplified := day19.SimplifyOperation(testSorter)
+	log.Printf("> simplivied %+v", simplified)
+* i probably don't need 'actual actors'
+just a generic function that takes 'detail' and 'sorterData'
+then applies sorterData to the detail,
+and calls itself with new sorter
+
+with special cases for "R" and "A"
+
+so. have funciton from OpeartionData & Detail -> true/false
+if true take the destination, if false, check next
+* well. only way to do this is with intervals
+
+so, sorter check takes in interval.
+
+then for each of the rule,
+call first rule with full interval,
+deduct first rule (for those that don't match) and pass to second.
+deduct second and pass to next
+
+A will return full
+R will return empty
+
+and results from each rule application should be joined
+
+so. i need interval deduction
+and i need interval join
+* found a bug in always using initial intervals to calculate 'failing' after each step
+2023/12/19 11:45:14 got and checked 167409079868000
+
+In the above example, there are 167409079868000 distinct combinations of ratings that will be accepted.

day19/sortingParts.go

@@ -0,0 +1,341 @@
+package day19
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"regexp"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+func Run() int {
+	fmt.Println("hello day 19. sorting parts")
+	filename := "day19/input"
+
+	bytes, err := os.ReadFile(filename)
+	if err != nil {
+		panic(fmt.Sprint("cannot read file ", filename))
+	}
+
+	text := string(bytes)
+
+	split := strings.Split(text, "\n\n")
+
+	sorters := ReadSorters(split[0])
+	details := ReadDetailsPart(split[1])
+
+	log.Printf("yay, got sorters\n%+v\nand details\n%+v", sorters, details)
+
+	// countApproved := CountApprovedDetails(details, sorters)
+	result := 0
+
+	fullIntervals := AttrIntervals{
+		"x": [][]int{[]int{1, 4000}},
+		"m": [][]int{[]int{1, 4000}},
+		"a": [][]int{[]int{1, 4000}},
+		"s": [][]int{[]int{1, 4000}},
+	}
+
+	andChecked := processInterval(fullIntervals, "in", sorters)
+	log.Print("got and checked ", andChecked)
+	result = andChecked
+
+	return result
+}
+
+func CountApprovedDetails(details []DetailData, sorters map[string]SorterData) int {
+	var wg sync.WaitGroup
+	wg.Add(len(details))
+
+	approvedDetails := make(chan DetailData)
+
+	go func() {
+		wg.Wait()
+		close(approvedDetails)
+	}()
+
+	count := 0
+	acceptedScore := 0
+
+	done := make(chan any)
+
+	go func() {
+		for detail := range approvedDetails {
+			log.Println("got approved ", detail)
+			count += 1
+			for _, attrValue := range detail.Attrs {
+				acceptedScore += attrValue
+			}
+		}
+		close(done)
+	}()
+
+	for _, d := range details {
+		go func(d DetailData) {
+			log.Print("> starting for ", d)
+			isAccepted := ProcessDetail(d, sorters)
+			if isAccepted {
+				log.Println("> accepting ", d)
+				approvedDetails <- d
+			} else {
+				log.Println("> rejecting ", d)
+			}
+			wg.Done()
+		}(d)
+	}
+
+	<-done
+
+	return acceptedScore
+}
+
+type Operation rune
+
+const (
+	LessThan Operation = '<'
+	MoreThan Operation = '>'
+)
+func (o Operation)String() string {
+	return string(o)
+}
+
+type OperationData struct {
+	AttrName   string
+	Operation  Operation
+	Num        int
+	SentToName string
+	InitialString     string
+}
+func (od OperationData)String() string {
+	return od.InitialString
+}
+
+type SorterData struct {
+	Name         string
+	DefaultState string
+	Operations   []OperationData
+}
+
+func ReadSorters(sortersText string) map[string]SorterData {
+	result := make(map[string]SorterData)
+	sortersText = strings.TrimSpace(sortersText)
+	lines := strings.Split(sortersText, "\n")
+
+	for _, line := range lines {
+		sorter := SimplifyOperation( ReadSorterLine(line) )
+		result[sorter.Name] = sorter
+	}
+
+	return result
+}
+
+// qqz{s>2770:qs,m<1801:hdj,R}
+func ReadSorterLine(line string) (result SorterData) {
+	re1 := regexp.MustCompile(`(?P<NAME>\D+){(?P<OPERATIONS>.+)}`)
+
+	firstSplit := re1.FindStringSubmatch(line)
+
+	result.Name = firstSplit[1]
+
+	operationLines := strings.Split(firstSplit[2], ",")
+	operations := make([]OperationData, len(operationLines)-1)
+	result.Operations = operations
+
+	result.DefaultState = operationLines[len(operationLines)-1]
+
+	for i, line := range operationLines[:len(operationLines)-1] {
+		operations[i] = ReadOperationLine(line)
+	}
+
+	log.Printf("mathed %s got %+v; operations : %+v\n", line, firstSplit, operations)
+
+	return
+}
+
+// s>2770:qs
+func ReadOperationLine(line string) (result OperationData) {
+	result.InitialString = line
+	re := regexp.MustCompile(`(?P<ATTRNAME>\D)(?P<OPERATION>[\>\<])(?P<NUMBER>\d+):(?P<TARGET>\D+)`)
+	split := re.FindStringSubmatch(line)
+	log.Printf("matching operation %s into %+v\n", line, split)
+	result.AttrName = split[1]
+	result.Operation = Operation([]rune(split[2])[0])
+	result.SentToName = split[4]
+	num, err := strconv.Atoi(split[3])
+	if err != nil {
+		panic(fmt.Sprintf("error getting number %s in line %s. %s", split[3], line, err))
+	}
+	result.Num = num
+	return
+}
+
+// drop last operations which target same 'next' as default. these check are not necessary
+func SimplifyOperation(sorter SorterData) SorterData {
+	actualLast := len(sorter.Operations) - 1
+	for i := actualLast; i >= 0; i-- {
+		if sorter.Operations[i].SentToName != sorter.DefaultState {
+			break
+		}
+		actualLast -= 1
+	}
+
+	sorter.Operations = sorter.Operations[:actualLast+1]
+
+	return sorter
+}
+
+type DetailData struct {
+	Attrs map[string]int
+}
+
+func ReadDetailsPart(text string) (result []DetailData) {
+	text = strings.TrimSpace(text)
+	for _, line := range strings.Split(text, "\n") {
+		result = append(result, ReadDetailLine(line))
+	}
+	return
+}
+
+// {x=787,m=2655,a=1222,s=2876}
+func ReadDetailLine(line string) (result DetailData) {
+	attrs := make(map[string]int)
+	result.Attrs = attrs
+	line = line[1 : len(line)-1]
+	attrsLine := strings.Split(line, ",")
+	re := regexp.MustCompile(`(?P<ATTR>\D)=(?P<NUM>\d+)`)
+	for _, attrLine := range attrsLine {
+		split := re.FindStringSubmatch(attrLine)
+		attrName := split[1]
+		num, err := strconv.Atoi(split[2])
+		if err != nil {
+			panic(fmt.Sprint("error parsing detail ", line))
+		}
+
+		attrs[attrName] = num
+	}
+	return
+}
+
+func ProcessDetail(d DetailData, sorters map[string]SorterData) (isAccepted bool) {
+	curSorterName := "in"
+	for curSorterName != "A" && curSorterName != "R" {
+		sorter, found := sorters[curSorterName]
+		if !found {
+			panic(fmt.Sprint("error finding soter ", curSorterName))
+		}
+		curSorterName = sorter.NextSorterNameFor(d)
+	}
+	return curSorterName == "A"
+}
+
+func (s SorterData) NextSorterNameFor(d DetailData) string {
+	for _, operation := range s.Operations {
+		if operation.IsDetailPassing(d) {
+			return operation.SentToName
+		}
+	}
+
+	return s.DefaultState
+}
+
+func (o OperationData) IsDetailPassing(d DetailData) bool {
+	detailValue := d.Attrs[o.AttrName]
+	switch o.Operation {
+	case LessThan:
+		return detailValue < o.Num
+	case MoreThan:
+		return detailValue > o.Num
+	}
+
+	panic(fmt.Sprint("unknown operation. ", o, d))
+}
+
+type AttrIntervals map[string][][]int
+
+func (o OperationData) getPassingIntervals(i AttrIntervals) AttrIntervals {
+	result := make(AttrIntervals, 0)
+	for key, value := range i {
+		result[key] = value
+	}
+
+	operationKey := o.AttrName
+	operatedIntervals := result[operationKey]
+
+	switch o.Operation {
+	case LessThan:
+		result[operationKey] = applyLessThan(operatedIntervals, o.Num)
+	case MoreThan:
+		result[operationKey] = applyMoreThan(operatedIntervals, o.Num)
+	}
+
+	return result
+}
+
+func (o OperationData) getFailingIntervals(i AttrIntervals) AttrIntervals {
+	result := make(AttrIntervals, 0)
+	for key, value := range i {
+		result[key] = value
+	}
+
+	operationKey := o.AttrName
+	operatedIntervals := result[operationKey]
+
+	switch o.Operation {
+	case LessThan:
+		result[operationKey] = applyMoreThan(operatedIntervals, o.Num-1)
+	case MoreThan:
+		result[operationKey] = applyLessThan(operatedIntervals, o.Num+1)
+	}
+
+	return result
+}
+
+func  processInterval(i AttrIntervals, sorterName string, sorters map[string]SorterData) (combinationsAccepted int) {
+	if sorterName == "A" {
+		mul := 1
+		for key, attrIntervals := range i {
+			allowedValuesOfAttr := 0
+			for _, interval := range attrIntervals {
+				from := interval[0]
+				to := interval[1]
+				len := to - from + 1
+				allowedValuesOfAttr += len
+				log.Printf("for %s allowed attrs are %d", key, allowedValuesOfAttr)
+			}
+			mul *= allowedValuesOfAttr
+		}
+		log.Printf("exit recursion for %s. Accept interval %+v . result %d. max is %d", sorterName, i, mul, 40000 * 4000 * 4000 * 4000)
+		return mul
+	}
+	if sorterName == "R" {
+		return 0
+	}
+
+	s := sorters[sorterName]
+	log.Printf("> starting interval check for %s (%+v) on %+v", sorterName, s, i)
+	intervalsPassingOnThisStep := i
+
+	for _, operation := range s.Operations {
+		intervalsPassing := operation.getPassingIntervals(intervalsPassingOnThisStep)
+		log.Printf(">> %s; in operation %+v. passing are %+v", sorterName, operation, intervalsPassing)
+		ofThoseAreAccepted := processInterval(intervalsPassing, operation.SentToName, sorters)
+
+		combinationsAccepted += ofThoseAreAccepted
+		log.Printf(">> %s; results so far are %d", sorterName, combinationsAccepted)
+
+		intervalsFailingAndPassedToNextCheck := operation.getFailingIntervals(intervalsPassingOnThisStep)
+		log.Printf(">> %s; failing for the next step %+v", sorterName, intervalsFailingAndPassedToNextCheck)
+		intervalsPassingOnThisStep = intervalsFailingAndPassedToNextCheck
+	}
+
+	log.Printf(">> %s; about to go into DEFAULT", sorterName)
+	intervalsAfterDefault := processInterval(intervalsPassingOnThisStep, s.DefaultState, sorters)
+	log.Printf(">> %s; after defaul. passing are %+v", sorterName, intervalsAfterDefault)
+	combinationsAccepted += intervalsAfterDefault
+	log.Printf(">> %s; results after default %d", sorterName, combinationsAccepted)
+
+	return
+}
+

main.go

@@ -3,12 +3,24 @@ package main
 import (
 	"log"
 
-	"sunshine.industries/aoc2023/day18"
+	"sunshine.industries/aoc2023/day19"
 )
 
 func main() {
 	log.Print("> starting run:")
 
-	result := day18.Run()
+	// lnx{m>1548:A,A}
-	log.Printf("\n\nday18 result: %d\n****\n", result)
+	// qqz{s>2770:qs,m<1801:hdj,R}
+	// kt{m>2215:R,x>3386:A,x<3107:R,R}
+	testSorter := day19.ReadSorterLine("kt{m>2215:R,x>3386:A,x<3107:R,R}")
+	log.Printf("my test sorter is %+v", testSorter)
+
+	simplified := day19.SimplifyOperation(testSorter)
+	log.Printf("> simplivied %+v", simplified)
+
+	detail := day19.ReadDetailLine("{x=787,m=2655,a=1222,s=2876}")
+	log.Printf("> detail %+v", detail)
+
+	result := day19.Run()
+	log.Printf("\n\nday19 result: %d\n****\n", result)
 }