feat: add day 6 2024

Reviewed-on: #23

.gitea/workflows/test.yml

@@ -28,6 +28,6 @@ jobs:
         go-version: 1.21.3
 
     - name: Test
-      run: go test --race -cover ./...
+      run: go test -timeout 240s -race -cover ./...
 
     - run: echo "🍏 This job's status is ${{ job.status }}."

README.md.sig

@@ -0,0 +1,6 @@
+-----BEGIN SSH SIGNATURE-----
+U1NIU0lHAAAAAQAAADMAAAALc3NoLWVkMjU1MTkAAAAgZ+OuJYdd3UiUbyBuO1RlsQR20a
+Qm5mKneuMxRjGo3zkAAAAEZmlsZQAAAAAAAAAGc2hhNTEyAAAAUwAAAAtzc2gtZWQyNTUx
+OQAAAED8T4C6WILXYZ1KxqDIlVhlrAEjr1Vc+tn8ypcVM3bN7iOexVvuUuvm90nr8eEwKU
+acrdDxmq2S+oysQbK+pMUE
+-----END SSH SIGNATURE-----

aoc2023/day01/main_test.go

@@ -30,7 +30,6 @@ func TestExample1(t *testing.T) {
 	is.Equal(result.sum, 142)
 }
 
-
 func TestExample2(t *testing.T) {
 	is := is.New(t)
 	scan := bufio.NewScanner(bytes.NewReader(example2))

aoc2023/day14/main.go

@@ -4,6 +4,7 @@ import (
 	"bufio"
 	_ "embed"
 	"fmt"
+	"slices"
 	"strings"
 
 	aoc "go.sour.is/advent-of-code"
@@ -62,7 +63,7 @@ func run(scan *bufio.Scanner) (*result, error) {
 					func(i int, v int, counts [3]int) [3]int {
 						counts[v]++
 						return counts
-					}, [3]int{}, maps.Values(memo)...)
+					}, [3]int{}, slices.Values(maps.Values(memo)))
 
 				// fmt.Println(i, counts)
 				i = 1_000_000_000 - (1_000_000_000-counts[0]-counts[1])%counts[2]

aoc2023/day14/main_test.go

@@ -36,11 +36,10 @@ func TestSolution(t *testing.T) {
 	is.NoErr(err)
 
 	t.Log(result)
- is.True(result.valuePT2 < 87286) // first submission
- is.True(result.valuePT2 < 87292) // second submission
- is.True(result.valuePT2 < 87287) // third submission
+	is.True(result.valuePT2 < 87286) // first submission
+	is.True(result.valuePT2 < 87292) // second submission
+	is.True(result.valuePT2 < 87287) // third submission
 
 	is.Equal(result.valuePT1, 110407)
 	is.Equal(result.valuePT2, 87273)
 }
-

aoc2023/day15/main.go

@@ -32,14 +32,14 @@ func run(scan *bufio.Scanner) (*result, error) {
 		r.valuePT1 = aoc.Reduce(func(i int, t string, sum int) int {
 			sum += hash(t)
 			return sum
-		}, 0, ops...)
+		}, 0, slices.Values(ops))
 	}
 
 	var boxen boxes
 
 	boxen = aoc.Reduce(func(i int, op string, b boxes) boxes {
 		return b.Op(op)
-	}, boxen, ops...)
+	}, boxen, slices.Values(ops))
 
 	r.valuePT2 = boxen.Sum()
 

aoc2023/day16/main.go

@@ -32,15 +32,15 @@ func run(scan *bufio.Scanner) (*result, error) {
 
 	options := make([]int, 2*(rows+cols)+2)
 	i := 0
-	for j:=0; j<=rows-1; j++ {
+	for j := 0; j <= rows-1; j++ {
 		options[i+0] = runCycle(m, ray{[2]int{j, -1}, RT})
 		options[i+1] = runCycle(m, ray{[2]int{j, cols}, LF})
-		i+=2
+		i += 2
 	}
-	for j:=0; j<=cols-1; j++ {
+	for j := 0; j <= cols-1; j++ {
 		options[i+0] = runCycle(m, ray{[2]int{-1, j}, DN})
 		options[i+1] = runCycle(m, ray{[2]int{rows, j}, UP})
-		i+=2
+		i += 2
 	}
 
 	// fmt.Println(options)
@@ -96,7 +96,6 @@ func (m *Map) Get(p [2]int) rune {
 	return (*m)[p[0]][p[1]]
 }
 
-
 func runCycle(m Map, r ray) int {
 	current := r
 

aoc2023/day17/main.go

@@ -0,0 +1,225 @@
+package main
+
+import (
+	"bufio"
+	_ "embed"
+	"fmt"
+
+	aoc "go.sour.is/advent-of-code"
+)
+
+var log = aoc.Log
+
+func main() { aoc.MustResult(aoc.Runner(run)) }
+
+type result struct {
+	valuePT1 int
+	valuePT2 int
+}
+
+func (r result) String() string { return fmt.Sprintf("%#v", r) }
+
+func run(scan *bufio.Scanner) (*result, error) {
+	var m aoc.Map[int16, rune]
+
+	for scan.Scan() {
+		text := scan.Text()
+		m = append(m, []rune(text))
+	}
+	log("start day 17")
+
+	result := result{}
+	result.valuePT1 = search(m, 1, 3, seenFn)
+	log("result from part 1 = ", result.valuePT1)
+
+	result.valuePT2 = search(m, 4, 10, nil)
+	log("result from part 2 = ", result.valuePT2)
+
+	return &result, nil
+}
+
+type Point = aoc.Point[int16]
+type Map = aoc.Map[int16, rune]
+
+// rotate for changing direction
+type rotate int8
+
+const (
+	CW  rotate = 1
+	CCW rotate = -1
+)
+
+// diretion of path steps
+type direction int8
+
+var (
+	U = Point{-1, 0}
+	R = Point{0, 1}
+	D = Point{1, 0}
+	L = Point{0, -1}
+)
+
+var directions = []Point{U, R, D, L}
+
+var directionIDX = func() map[Point]direction {
+	m := make(map[Point]direction, len(directions))
+	for k, v := range directions {
+		m[v] = direction(k)
+	}
+	return m
+}()
+
+// position on the map
+type position struct {
+	loc       Point
+	direction Point
+	steps     int8
+}
+
+func (p position) step() position {
+	return position{p.loc.Add(p.direction), p.direction, p.steps + 1}
+}
+func (p position) rotateAndStep(towards rotate) position {
+	d := directions[(int8(directionIDX[p.direction])+int8(towards)+4)%4]
+	return position{p.loc.Add(d), d, 1}
+}
+
+// implements FindPath graph interface
+type graph struct {
+	min, max int8
+	m        Map
+	target   Point
+	reads    int
+	seenFn   func(a position) position
+}
+
+// Neighbors returns valid steps from given position. if at target returns none.
+func (g *graph) Neighbors(current position) []position {
+	var nbs []position
+
+	if current.steps == 0 {
+		return []position{
+			{R, R, 1},
+			{D, D, 1},
+		}
+	}
+
+	if current.loc == g.target {
+		return nil
+	}
+
+	if left := current.rotateAndStep(CCW); current.steps >= g.min && g.m.Valid(left.loc) {
+		nbs = append(nbs, left)
+	}
+
+	if right := current.rotateAndStep(CW); current.steps >= g.min && g.m.Valid(right.loc) {
+		nbs = append(nbs, right)
+	}
+
+	if forward := current.step(); current.steps < g.max && g.m.Valid(forward.loc) {
+		nbs = append(nbs, forward)
+	}
+
+	return nbs
+}
+
+// Cost calculates heat cost to neighbor from map
+func (g *graph) Cost(a, b position) int16 {
+	g.reads++
+	_, r, _ := g.m.Get(b.loc)
+	return int16(r - '0')
+}
+
+// Potential calculates distance to target
+// func (g *graph) Potential(a position) int16 {
+// 	return aoc.ManhattanDistance(a.loc, g.target)
+// }
+
+// Target returns true when target reached. receives node and cost.
+func (g *graph) Target(a position, c int16) bool {
+	if a.loc == g.target && a.steps >= g.min && a.steps <= g.max {
+		return true
+	}
+	return false
+}
+
+// Seen attempt at simplifying the seen to use horizontal/vertical and no steps.
+// It returns correct for part1 but not part 2..
+func (g *graph) Seen(a position) position {
+	if g.seenFn != nil {
+		return g.seenFn(a)
+	}
+	return a
+}
+
+func seenFn(a position) position {
+	if a.direction == U {
+		a.direction = D
+	}
+	if a.direction == L {
+		a.direction = R
+	}
+	// a.steps = 0
+	return a
+}
+
+func search(m Map, minSteps, maxSteps int8, seenFn func(position) position) int {
+	rows, cols := m.Size()
+	start := Point{}
+	target := Point{rows - 1, cols - 1}
+
+	g := graph{min: minSteps, max: maxSteps, m: m, target: target, seenFn: seenFn}
+
+	cost, path, closed := aoc.FindPath[int16, position](&g, position{loc: start}, position{loc: target})
+
+	log("total map reads = ", g.reads, "cost = ", cost)
+	printGraph(m, path, closed, g.seenFn)
+
+	return int(cost)
+}
+
+// printGraph with the path/cost overlay
+func printGraph(m Map, path []position, closed map[position]int16, seenFn func(a position) position) {
+	pts := make(map[Point]position, len(path))
+	for _, pt := range path {
+		pts[pt.loc] = pt
+	}
+
+	clpt := make(map[position]position, len(closed))
+	for pt := range closed {
+		clpt[position{loc: pt.loc, steps: pt.steps}] = pt
+	}
+
+	for r, row := range m {
+		// if r == 0 {
+		// 	for c := range row {
+		// 		if c == 0 {
+		// 			fmt.Print("     ")
+		// 		}
+		// 		fmt.Printf("% 5d", c)
+		// 	}
+		// 	fmt.Println("")
+		// }
+		for c := range row {
+			// if c == 0 {
+			// 	fmt.Printf("% 5d", r)
+			// }
+
+			if pt, ok := pts[Point{int16(r), int16(c)}]; ok {
+				if seenFn != nil {
+					pt = seenFn(pt)
+				}
+				_ = pt
+				// fmt.Printf("% 5d", closed[pt])
+				fmt.Print("*")
+
+				continue
+			}
+
+			// fmt.Print(" ....")
+			fmt.Print(" ")
+		}
+		fmt.Println("")
+	}
+	fmt.Println("")
+}

aoc2023/day17/main_test.go

@@ -0,0 +1,41 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"testing"
+
+	_ "embed"
+
+	"github.com/matryer/is"
+)
+
+//go:embed example.txt
+var example []byte
+
+//go:embed input.txt
+var input []byte
+
+func TestExample(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(example))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 102)
+	is.Equal(result.valuePT2, 94)
+}
+
+func TestSolution(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(input))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 843)
+	is.Equal(result.valuePT2, 1017)
+}

aoc2023/day18/example.txt

@@ -0,0 +1,14 @@
+R 6 (#70c710)
+D 5 (#0dc571)
+L 2 (#5713f0)
+D 2 (#d2c081)
+R 2 (#59c680)
+D 2 (#411b91)
+L 5 (#8ceee2)
+U 2 (#caa173)
+L 1 (#1b58a2)
+U 2 (#caa171)
+R 2 (#7807d2)
+U 3 (#a77fa3)
+L 2 (#015232)
+U 2 (#7a21e3)

aoc2023/day18/input.txt

@@ -0,0 +1,766 @@
+R 4 (#0a7a60)
+U 8 (#4453b3)
+R 6 (#8e4f70)
+U 2 (#4453b1)
+R 4 (#0feb00)
+U 4 (#355591)
+R 8 (#2a09c0)
+U 4 (#544c71)
+R 4 (#472930)
+U 2 (#199e33)
+R 3 (#3d8df0)
+U 5 (#199e31)
+R 7 (#45de50)
+U 4 (#57a941)
+L 7 (#671c70)
+U 5 (#5e5e81)
+R 4 (#2e9b60)
+U 8 (#490881)
+L 7 (#1846f0)
+U 3 (#304101)
+L 4 (#1846f2)
+D 2 (#58f3f1)
+L 9 (#2e9b62)
+D 2 (#56dcd1)
+L 2 (#671c72)
+D 9 (#275fd1)
+L 4 (#76b7b2)
+U 9 (#5b9641)
+L 4 (#1d3212)
+U 10 (#3d1841)
+L 3 (#5ad5e2)
+D 6 (#010211)
+L 5 (#13ec52)
+D 8 (#166471)
+L 3 (#53ebc0)
+D 5 (#0fdba1)
+L 4 (#54e450)
+D 9 (#440a21)
+L 3 (#49b242)
+D 5 (#2f0171)
+L 6 (#447332)
+D 4 (#182561)
+L 8 (#1aaaa2)
+D 6 (#0996a1)
+L 4 (#1c1212)
+D 6 (#5780d1)
+L 7 (#0fc1d2)
+D 7 (#36cb41)
+L 3 (#505552)
+D 7 (#8d8b81)
+R 4 (#2bf742)
+D 7 (#152791)
+R 5 (#760492)
+D 3 (#11a991)
+R 3 (#5debc0)
+D 10 (#59f211)
+L 4 (#66d342)
+D 8 (#1fc6b1)
+R 4 (#66d340)
+D 6 (#72dff1)
+L 2 (#3f1b10)
+D 4 (#2fca13)
+L 10 (#2d0162)
+D 5 (#8b5e53)
+L 6 (#2d0160)
+U 2 (#317053)
+L 2 (#650c20)
+U 7 (#2bed01)
+R 10 (#409ed0)
+U 2 (#166713)
+L 10 (#939350)
+U 6 (#166711)
+L 4 (#38a180)
+D 3 (#1d95f1)
+L 6 (#11ea60)
+D 5 (#931dc1)
+R 6 (#11bf70)
+D 7 (#536051)
+L 3 (#995b60)
+D 2 (#254e91)
+L 3 (#332fd2)
+U 6 (#7669f1)
+L 3 (#574642)
+U 6 (#1778a1)
+L 3 (#1a00c2)
+U 5 (#2eaa81)
+L 3 (#1cf8e2)
+U 6 (#0c71a1)
+L 6 (#868472)
+U 3 (#0a9fd1)
+R 9 (#104c02)
+U 4 (#082451)
+L 7 (#850d02)
+U 6 (#082453)
+L 7 (#322552)
+U 3 (#1339d1)
+L 6 (#8e11d2)
+U 4 (#6c5691)
+R 6 (#1dda10)
+U 3 (#25e5c3)
+R 7 (#370670)
+U 4 (#9324f1)
+L 3 (#451030)
+U 7 (#1f1021)
+L 7 (#0ba3c0)
+U 5 (#8a10a3)
+L 8 (#67db30)
+U 5 (#282473)
+L 4 (#0cd350)
+U 4 (#25e5c1)
+R 3 (#6b4ee0)
+U 4 (#333cf1)
+R 5 (#02b610)
+D 4 (#4e7cc1)
+R 3 (#92abb0)
+U 5 (#2f6ff1)
+R 5 (#483360)
+U 5 (#7b1cd1)
+L 8 (#3a5d50)
+U 3 (#1d2461)
+R 8 (#3b2fd0)
+U 5 (#630763)
+R 6 (#5033c0)
+U 3 (#252523)
+R 7 (#08eeb0)
+U 8 (#516633)
+L 7 (#156240)
+U 4 (#2db063)
+L 3 (#791070)
+D 5 (#2920a3)
+L 3 (#0dafe0)
+U 5 (#4185b3)
+L 5 (#7ac0e0)
+U 2 (#5a6cd3)
+L 2 (#3ca790)
+U 7 (#755403)
+L 4 (#3b0740)
+U 5 (#2004a3)
+L 3 (#2db4f0)
+U 6 (#602a23)
+R 5 (#32c1c0)
+D 2 (#000f53)
+R 5 (#388360)
+D 7 (#24d9e3)
+R 4 (#4703a0)
+D 3 (#2f1133)
+R 3 (#4703a2)
+U 11 (#52e853)
+R 5 (#278132)
+D 11 (#0665e3)
+R 3 (#239112)
+U 6 (#8f0ad1)
+R 5 (#447de2)
+U 6 (#8f0ad3)
+R 6 (#636122)
+U 2 (#187283)
+R 3 (#5aae62)
+U 10 (#1d8833)
+L 5 (#476db0)
+U 5 (#136393)
+L 7 (#29e6b0)
+U 5 (#136391)
+R 7 (#3ba060)
+U 3 (#635e23)
+L 5 (#2042f0)
+U 3 (#181643)
+L 6 (#5af952)
+U 8 (#28d0b1)
+L 2 (#4a98f2)
+U 9 (#28d0b3)
+L 6 (#27a572)
+D 3 (#3d7213)
+L 4 (#516842)
+D 11 (#21ef63)
+L 5 (#38e342)
+D 2 (#1118b3)
+L 3 (#560502)
+D 9 (#1118b1)
+R 2 (#1c39a2)
+D 2 (#303ab3)
+R 6 (#716ba0)
+D 6 (#780a93)
+L 8 (#77ec30)
+U 2 (#780a91)
+L 3 (#271100)
+U 10 (#5882f3)
+L 4 (#2050c2)
+D 3 (#434843)
+L 3 (#7d9572)
+D 2 (#3129b3)
+L 5 (#21fb12)
+D 5 (#8c2c33)
+L 4 (#57bf92)
+D 6 (#2730b3)
+L 4 (#6a3902)
+D 8 (#4656a3)
+L 5 (#60ac80)
+D 4 (#43b863)
+R 9 (#3d69a0)
+D 8 (#3ca913)
+L 2 (#411d80)
+D 3 (#725383)
+L 8 (#4a98d0)
+D 9 (#274553)
+L 5 (#580d60)
+U 5 (#568223)
+L 6 (#473af0)
+U 5 (#827593)
+L 7 (#251dc2)
+U 5 (#0fcea3)
+L 8 (#5ae3d2)
+U 3 (#4efa11)
+R 9 (#389852)
+U 2 (#7f7f91)
+R 6 (#618342)
+U 3 (#441143)
+L 7 (#886df2)
+U 3 (#26a093)
+L 8 (#886df0)
+U 4 (#63c7d3)
+L 3 (#04f842)
+D 10 (#0fcea1)
+L 6 (#388e62)
+U 10 (#3ae7f3)
+L 3 (#2a6880)
+U 6 (#3bfd53)
+L 6 (#73a0c0)
+U 5 (#3bfd51)
+L 4 (#0d18a0)
+U 2 (#19da93)
+L 6 (#120600)
+U 8 (#233b53)
+L 6 (#2e1050)
+U 3 (#4b2aa3)
+L 4 (#5f9930)
+U 10 (#6e65f1)
+R 6 (#1eefa0)
+U 9 (#50b9d3)
+R 2 (#548ed0)
+U 9 (#50b9d1)
+R 7 (#8bd9f0)
+U 4 (#5ae473)
+R 6 (#0b0490)
+U 10 (#186891)
+R 4 (#764830)
+U 7 (#33b0e1)
+R 5 (#363c90)
+U 8 (#7bd631)
+R 7 (#031e30)
+U 7 (#095881)
+R 3 (#640e50)
+D 5 (#02e7f3)
+R 7 (#0922f0)
+D 7 (#6b7af3)
+R 9 (#0922f2)
+D 3 (#62e543)
+R 3 (#21e320)
+U 9 (#5ead81)
+R 7 (#01fd70)
+D 9 (#3b0cf1)
+R 2 (#2758a0)
+D 5 (#7279b1)
+R 8 (#5c7dc0)
+D 7 (#3c8db1)
+R 4 (#3c3740)
+U 2 (#26b151)
+R 6 (#11eb12)
+U 4 (#587921)
+R 6 (#11eb10)
+U 4 (#320051)
+R 4 (#038630)
+U 3 (#6a2e61)
+R 2 (#4ff680)
+U 5 (#3c57f1)
+R 9 (#0b2440)
+U 8 (#497533)
+L 6 (#704680)
+U 11 (#549113)
+R 6 (#23b470)
+U 4 (#9e0641)
+R 7 (#1aeec0)
+D 7 (#4a6331)
+R 2 (#547d80)
+D 5 (#457a71)
+R 9 (#7daa90)
+D 4 (#16d7b1)
+L 6 (#266810)
+D 3 (#363561)
+L 5 (#5312b2)
+D 4 (#42c301)
+R 5 (#9a0952)
+D 7 (#42c303)
+R 7 (#7d1df2)
+D 4 (#51e321)
+R 5 (#609422)
+D 4 (#3b8f01)
+R 6 (#644792)
+U 4 (#2d8b11)
+R 7 (#22bbc2)
+D 7 (#6b39b1)
+R 5 (#680e72)
+U 2 (#7f9f31)
+R 3 (#0e9b52)
+U 3 (#3086c1)
+R 3 (#5a60c0)
+U 6 (#53b6e3)
+R 7 (#8117d0)
+U 7 (#53b6e1)
+R 3 (#2cb930)
+U 3 (#1bffd1)
+R 6 (#4539f0)
+U 8 (#680411)
+R 4 (#6032c0)
+U 6 (#255061)
+R 3 (#5562a0)
+U 6 (#088071)
+R 3 (#3bf2f0)
+U 5 (#52bdb1)
+L 6 (#070500)
+U 5 (#69e001)
+R 6 (#070502)
+U 3 (#071051)
+R 2 (#036000)
+U 4 (#0ea8a1)
+R 5 (#05e4d0)
+U 3 (#674de1)
+R 3 (#804250)
+D 6 (#3ffca1)
+R 4 (#23dcb2)
+D 6 (#9f9841)
+L 5 (#45f210)
+D 9 (#15efc1)
+R 5 (#45f212)
+D 4 (#969551)
+L 9 (#23dcb0)
+D 2 (#41bea1)
+L 4 (#2f2a32)
+D 4 (#71ffd1)
+R 3 (#5c0bb2)
+D 7 (#6f3501)
+R 4 (#2b0a72)
+D 4 (#7b3571)
+R 3 (#1c67d2)
+U 11 (#42f011)
+R 3 (#51ae62)
+D 3 (#75fcf1)
+R 3 (#1f4742)
+D 4 (#2813f1)
+R 4 (#3d1812)
+D 2 (#2b1d01)
+R 11 (#1eb302)
+U 3 (#27b0a1)
+R 4 (#227b20)
+U 5 (#34b7e1)
+R 10 (#201220)
+U 7 (#0502f3)
+R 4 (#5ab7f0)
+U 4 (#0502f1)
+R 4 (#5d09b0)
+U 7 (#504a81)
+R 7 (#1e8250)
+U 3 (#715aa1)
+R 6 (#26d290)
+U 6 (#9a12f1)
+L 3 (#18be90)
+U 8 (#037d11)
+L 5 (#647600)
+U 3 (#40b983)
+L 5 (#04e450)
+U 3 (#9a9a43)
+L 8 (#04e452)
+U 6 (#8af153)
+R 8 (#6cbc90)
+U 4 (#04d121)
+L 4 (#285292)
+U 3 (#688d51)
+L 6 (#176332)
+U 4 (#400a91)
+L 5 (#176330)
+U 5 (#43def1)
+R 2 (#285290)
+U 2 (#3e0711)
+R 3 (#7eb9c0)
+U 7 (#36f611)
+R 7 (#666af0)
+D 7 (#381b31)
+R 3 (#298922)
+U 3 (#475671)
+R 6 (#977c12)
+D 4 (#602d01)
+R 6 (#25b0c2)
+D 6 (#7ede81)
+R 3 (#1d58c2)
+D 8 (#873523)
+L 9 (#265ae2)
+D 3 (#57d663)
+R 7 (#1565c2)
+D 8 (#06ed11)
+R 4 (#a348c2)
+D 2 (#06ed13)
+R 8 (#12d052)
+D 4 (#2d3741)
+L 7 (#0ccfd2)
+D 3 (#1fcd61)
+R 4 (#39a4c2)
+D 3 (#44f7f1)
+R 6 (#5c3202)
+D 8 (#2625c1)
+L 8 (#2b08c2)
+D 2 (#20d7e1)
+L 2 (#67b892)
+D 10 (#546471)
+R 7 (#484ef2)
+D 7 (#49bc91)
+R 4 (#91aa72)
+U 11 (#499591)
+R 3 (#0048b2)
+U 7 (#34a7a1)
+R 7 (#514600)
+U 8 (#1cdc43)
+L 7 (#471470)
+U 3 (#8c8393)
+R 3 (#18a780)
+U 5 (#8c8391)
+R 3 (#4e6f80)
+U 3 (#1cdc41)
+R 8 (#428930)
+U 5 (#5dcb51)
+R 3 (#4b21e2)
+U 4 (#0464b1)
+R 9 (#850552)
+D 8 (#464881)
+R 7 (#543852)
+D 3 (#2d3a11)
+R 3 (#081b22)
+D 5 (#0cc731)
+R 7 (#6990e0)
+D 3 (#79d7b1)
+R 3 (#509520)
+D 5 (#438571)
+R 3 (#27d510)
+D 3 (#30d2d3)
+L 8 (#1b7a00)
+D 5 (#8a0da3)
+L 8 (#1b7a02)
+U 5 (#027cb3)
+L 7 (#350130)
+D 8 (#2ff771)
+R 7 (#16dc02)
+D 2 (#68f1c1)
+R 5 (#02f782)
+D 6 (#4e2a41)
+R 11 (#448e32)
+D 5 (#2cfac1)
+L 11 (#417502)
+D 5 (#2cfac3)
+L 4 (#22f022)
+U 9 (#1e9f01)
+L 5 (#543572)
+U 3 (#076e31)
+L 6 (#081b20)
+U 5 (#1ae851)
+L 3 (#823132)
+U 9 (#2d7993)
+L 4 (#5738f2)
+D 8 (#79e273)
+L 4 (#5c9ad2)
+D 8 (#4ed1b3)
+L 3 (#311722)
+D 4 (#0d5493)
+L 6 (#5d63e0)
+D 6 (#178cf3)
+L 5 (#75b1b0)
+D 5 (#178cf1)
+L 6 (#11d550)
+D 6 (#44ed03)
+L 3 (#76a842)
+U 6 (#3b6993)
+L 5 (#184892)
+D 4 (#5c8163)
+L 3 (#14d872)
+U 2 (#261a01)
+L 5 (#2d01e2)
+U 9 (#326ca3)
+L 4 (#59ad32)
+U 8 (#326ca1)
+R 4 (#389ab2)
+U 9 (#261a03)
+L 4 (#50cb42)
+D 4 (#2f8263)
+L 5 (#9f3752)
+D 6 (#4bb383)
+L 4 (#2693f2)
+D 4 (#19dca3)
+R 4 (#475bc2)
+D 6 (#960e13)
+L 7 (#0c90a2)
+D 8 (#3463d3)
+L 6 (#5a82e2)
+D 3 (#5a5c43)
+R 7 (#120bf2)
+D 3 (#5069e3)
+R 3 (#4b47a2)
+D 6 (#635b63)
+R 4 (#66ca10)
+U 4 (#1418f1)
+R 7 (#1d5470)
+D 4 (#1418f3)
+R 8 (#66d4f0)
+D 5 (#3c5533)
+R 4 (#2f6e02)
+D 3 (#2cf5e3)
+R 4 (#633ec2)
+D 7 (#2cf5e1)
+R 7 (#5846b2)
+D 3 (#4f9d63)
+R 4 (#533380)
+D 11 (#13c7e3)
+R 2 (#222b62)
+D 3 (#928ab3)
+R 5 (#222b60)
+U 5 (#0a4793)
+R 5 (#15d3b0)
+U 8 (#363fe1)
+R 4 (#2feb30)
+U 5 (#05d8b1)
+R 3 (#39e030)
+U 3 (#05d8b3)
+R 2 (#3cd780)
+U 8 (#02c781)
+R 5 (#186452)
+D 3 (#37bba1)
+R 5 (#9e1232)
+D 5 (#58e6f1)
+R 5 (#182c30)
+D 5 (#072db1)
+R 5 (#85e600)
+D 4 (#607651)
+R 5 (#186450)
+D 3 (#0aca91)
+L 5 (#0ceb10)
+D 5 (#860001)
+L 6 (#54c8b0)
+U 5 (#393971)
+L 4 (#37c390)
+D 3 (#1f1433)
+L 5 (#3d8790)
+D 6 (#353623)
+R 4 (#78c830)
+D 4 (#6fafa3)
+R 6 (#2b0612)
+D 5 (#31fff3)
+R 7 (#8b49b2)
+D 9 (#6f0ee3)
+R 5 (#4212e0)
+D 6 (#5d11f3)
+R 6 (#648340)
+D 8 (#393743)
+R 6 (#34ddd0)
+U 8 (#346fb3)
+R 5 (#34fc22)
+D 4 (#71c453)
+R 6 (#5048f2)
+D 4 (#0bb993)
+R 4 (#42b9f0)
+D 9 (#5cdf83)
+R 5 (#42b9f2)
+D 3 (#6f3f93)
+R 3 (#3dbae2)
+D 8 (#495363)
+R 9 (#328ba2)
+D 3 (#77afa1)
+R 5 (#575710)
+D 2 (#10d861)
+R 4 (#257822)
+D 4 (#6efe61)
+R 9 (#257820)
+D 5 (#521d01)
+R 5 (#575712)
+D 6 (#494cf1)
+L 5 (#683ab2)
+D 4 (#5e79c3)
+L 3 (#4242a2)
+D 4 (#5e79c1)
+L 7 (#2c3442)
+D 8 (#2fbd23)
+L 5 (#636fb2)
+D 5 (#63bd53)
+L 2 (#299960)
+D 6 (#31ea33)
+R 3 (#51dfb0)
+D 7 (#4e4ec3)
+R 4 (#7b7912)
+D 5 (#4b4bf3)
+R 4 (#54e882)
+D 5 (#7d2193)
+R 3 (#3b77d2)
+D 3 (#826973)
+R 8 (#646ec2)
+D 4 (#076c63)
+L 10 (#674052)
+D 6 (#3676b1)
+L 9 (#3bd890)
+D 4 (#7feb71)
+L 3 (#3bd892)
+D 3 (#27fc21)
+R 8 (#66bba2)
+D 8 (#645c73)
+R 5 (#43e132)
+D 5 (#51d9e3)
+R 8 (#43e130)
+D 6 (#2827f3)
+R 4 (#412c92)
+D 5 (#7e7f63)
+L 4 (#218122)
+D 4 (#546e83)
+L 9 (#82f672)
+D 8 (#6ed383)
+L 3 (#701412)
+D 7 (#47de23)
+L 5 (#46f912)
+D 7 (#0d9ec3)
+L 4 (#515142)
+D 3 (#4699e3)
+L 9 (#2ed562)
+U 6 (#00a273)
+L 9 (#8d7d12)
+U 2 (#6c3a83)
+L 7 (#318fa2)
+U 7 (#0bd473)
+L 2 (#6d5050)
+U 10 (#415673)
+R 3 (#9e8420)
+U 6 (#1ff213)
+R 5 (#0c8bf0)
+U 2 (#479a11)
+R 6 (#977360)
+U 5 (#479a13)
+L 8 (#250680)
+U 2 (#1ff211)
+L 3 (#216630)
+U 3 (#22d143)
+L 3 (#3b4342)
+U 7 (#9d4ff3)
+L 5 (#43aca2)
+U 6 (#29efd3)
+L 3 (#5c6a12)
+D 11 (#134a73)
+L 6 (#2a0982)
+U 11 (#444723)
+L 4 (#47e2e2)
+U 4 (#6855c3)
+L 4 (#06a382)
+U 4 (#2222e3)
+R 3 (#4edc62)
+U 6 (#9a2683)
+R 6 (#131872)
+U 10 (#4f5a23)
+R 4 (#858f70)
+U 5 (#4d4823)
+L 9 (#3f73f0)
+U 3 (#46f5a3)
+L 4 (#935370)
+U 4 (#46f5a1)
+L 5 (#3ca140)
+U 6 (#07b1e3)
+L 5 (#61ecd0)
+U 5 (#654743)
+L 5 (#3cec42)
+U 6 (#30bb83)
+R 3 (#920782)
+U 6 (#1f9323)
+R 8 (#3d8aa2)
+U 8 (#7492c3)
+R 3 (#301cd2)
+U 3 (#32e2f1)
+R 4 (#6936f2)
+U 6 (#32e2f3)
+R 6 (#5112c2)
+U 7 (#535b53)
+L 10 (#61f4d0)
+U 3 (#915863)
+L 2 (#51d540)
+U 5 (#32dee1)
+L 10 (#4ec320)
+U 5 (#406bc1)
+L 2 (#1b3890)
+U 3 (#681181)
+L 6 (#35ed60)
+D 9 (#153fd3)
+L 5 (#323e30)
+U 5 (#381ad3)
+L 3 (#69a550)
+U 3 (#310f63)
+L 4 (#2cbb80)
+U 5 (#3448a3)
+R 6 (#206282)
+U 5 (#202ab1)
+L 6 (#83af82)
+U 4 (#202ab3)
+L 4 (#248d02)
+D 9 (#28a983)
+L 4 (#32cf10)
+D 7 (#249d73)
+R 4 (#2f5c70)
+D 6 (#021c93)
+L 7 (#957782)
+D 6 (#550e53)
+R 5 (#957780)
+D 6 (#50bb13)
+R 9 (#49b7f2)
+U 6 (#096e93)
+R 4 (#769452)
+D 3 (#6dc543)
+R 5 (#2ad352)
+D 7 (#167963)
+L 10 (#673682)
+D 5 (#152883)
+L 10 (#13f332)
+D 3 (#996721)
+L 4 (#4be2a2)
+D 4 (#9c2443)
+L 4 (#2b83b0)
+D 3 (#5d63b3)
+L 9 (#9cfd40)
+D 7 (#49e793)
+L 7 (#0b5422)
+D 8 (#5c51b3)
+L 2 (#6db152)
+D 4 (#215b53)
+L 3 (#38dc12)
+D 8 (#7dad01)
+L 6 (#559e22)
+D 3 (#929d23)
+L 2 (#0f7560)
+D 6 (#448d13)
+L 7 (#73a972)
+D 2 (#2221c3)
+L 3 (#73a970)
+D 5 (#53b553)
+R 10 (#513590)
+D 3 (#293c83)
+L 10 (#58e2e0)
+D 4 (#54dd21)
+L 5 (#1bcdf2)
+D 5 (#4b0b71)
+L 5 (#1bcdf0)
+U 6 (#43b811)
+L 5 (#4df1d0)
+U 6 (#36d6a3)
+R 5 (#3bfb20)
+U 5 (#75de61)
+L 5 (#1e0ec2)
+U 4 (#30b571)
+L 7 (#2dfd20)
+D 5 (#49ad61)
+L 2 (#2dfd22)
+D 11 (#715d41)
+L 3 (#1e0ec0)
+U 4 (#0f2091)
+L 4 (#9d29c0)
+U 9 (#475a73)
+L 2 (#108610)
+U 3 (#1e5423)
+L 8 (#394192)
+U 3 (#0274b3)

aoc2023/day18/main.go

@@ -0,0 +1,89 @@
+package main
+
+import (
+	"bufio"
+	_ "embed"
+	"fmt"
+	"strconv"
+	"strings"
+
+	aoc "go.sour.is/advent-of-code"
+	"golang.org/x/exp/maps"
+)
+
+// var log = aoc.Log
+
+func main() { aoc.MustResult(aoc.Runner(run)) }
+
+type result struct {
+	valuePT1 int
+	valuePT2 int
+}
+
+func (r result) String() string { return fmt.Sprintf("%#v", r) }
+
+func run(scan *bufio.Scanner) (*result, error) {
+
+	var vecsPT1 []aoc.Vector
+	var vecsPT2 []aoc.Vector
+
+	for scan.Scan() {
+		text := scan.Text()
+
+		if len(text) == 0 {
+			continue
+		}
+
+		v, color := fromLine(text)
+
+		vecsPT1 = append(vecsPT1, v)
+		vecsPT2 = append(vecsPT2, fromColor(color))
+	}
+	return &result{
+		valuePT1: findArea(vecsPT1),
+		valuePT2: findArea(vecsPT2),
+	}, nil
+}
+
+var OFFSET = map[string]aoc.Point[int]{
+	"R": {0, 1},
+	"D": {1, 0},
+	"L": {0, -1},
+	"U": {-1, 0},
+}
+var OFFSET_INDEXES = maps.Values(OFFSET)
+
+func fromLine(text string) (aoc.Vector, string) {
+	v := aoc.Vector{}
+	s, text, _ := strings.Cut(text, " ")
+	v.Offset = OFFSET[s]
+
+	s, text, _ = strings.Cut(text, " ")
+	v.Scale = aoc.Atoi(s)
+
+	_, text, _ = strings.Cut(text, "(#")
+	s, _, _ = strings.Cut(text, ")")
+	return v, s
+}
+
+func fromColor(c string) aoc.Vector {
+	scale, _ := strconv.ParseInt(c[:5], 16, 64)
+	offset := OFFSET_INDEXES[c[5]-'0']
+
+	return aoc.Vector{
+		Offset: offset,
+		Scale:  int(scale),
+	}
+}
+
+func findArea(vecs []aoc.Vector) int {
+	shoelace := []aoc.Point[int]{{0, 0}}
+	borderLength := 0
+
+	for _, vec := range vecs {
+		shoelace = append(shoelace, shoelace[len(shoelace)-1].Add(vec.Point()))
+		borderLength += vec.Scale
+	}
+
+	return aoc.NumPoints(shoelace, borderLength)
+}

aoc2023/day18/main_test.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"testing"
+
+	_ "embed"
+
+	"github.com/matryer/is"
+)
+
+//go:embed example.txt
+var example []byte
+
+//go:embed input.txt
+var input []byte
+
+func TestExample(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(example))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 62)
+	is.Equal(result.valuePT2, 952408144115)
+}
+
+func TestSolution(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(input))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.True(result.valuePT1 < 68834) // first attempt too high.
+	is.Equal(result.valuePT1, 46334)
+	is.Equal(result.valuePT2, 102000662718092)
+}

aoc2023/day19/main.go

@@ -0,0 +1,255 @@
+package main
+
+import (
+	"bufio"
+	_ "embed"
+	"fmt"
+	"strings"
+
+	aoc "go.sour.is/advent-of-code"
+)
+
+// var log = aoc.Log
+
+func main() { aoc.MustResult(aoc.Runner(run)) }
+
+type result struct {
+	valuePT1 int
+	valuePT2 uint
+}
+
+func (r result) String() string { return fmt.Sprintf("%#v", r) }
+
+func run(scan *bufio.Scanner) (*result, error) {
+
+	var workflows = make(map[string][]rule)
+	var parts []part
+
+	for scan.Scan() {
+		text := strings.TrimSuffix(scan.Text(), "}")
+		if len(text) == 0 {
+			continue
+		}
+
+		// Is Part
+		if p, ok := scanPart(text); ok {
+			parts = append(parts, p)
+			continue
+		}
+
+		if name, r, ok := scanRule(text); ok {
+			workflows[name] = r
+		}
+	}
+
+	var result result
+	result.valuePT1 = solveWorkflow(parts, workflows)
+	result.valuePT2 = solveRanges(workflows)
+
+	return &result, nil
+}
+
+type part struct {
+	x, m, a, s int
+}
+
+func (p part) String() string {
+	return fmt.Sprintf("{x:%v m:%v a:%v s:%v}", p.x, p.m, p.a, p.s)
+}
+func scanPart(text string) (part, bool) {
+	var p part
+
+	// Is Part
+	if text[0] == '{' {
+		for _, s := range strings.Split(text[1:], ",") {
+			a, b, _ := strings.Cut(s, "=")
+			i := aoc.Atoi(b)
+			switch a {
+			case "x":
+				p.x = i
+			case "m":
+				p.m = i
+			case "a":
+				p.a = i
+			case "s":
+				p.s = i
+			}
+		}
+		return p, true
+	}
+	return p, false
+}
+
+type rule struct {
+	match string
+	op    string
+	value int
+	queue string
+}
+
+func scanRule(text string) (string, []rule, bool) {
+	name, text, _ := strings.Cut(text, "{")
+	var r []rule
+	for _, s := range strings.Split(text, ",") {
+		if a, b, ok := strings.Cut(s, "<"); ok {
+			b, c, _ := strings.Cut(b, ":")
+			r = append(r, rule{
+				match: a,
+				op:    "<",
+				value: aoc.Atoi(b),
+				queue: c,
+			})
+
+			continue
+		}
+		if a, b, ok := strings.Cut(s, ">"); ok {
+			b, c, _ := strings.Cut(b, ":")
+			r = append(r, rule{
+				match: a,
+				op:    ">",
+				value: aoc.Atoi(b),
+				queue: c,
+			})
+			continue
+		}
+
+		// default queue comes last
+		r = append(r, rule{queue: s})
+		break
+	}
+	return name, r, len(r) > 0
+}
+func (r rule) Match(p part) bool {
+	var value int
+
+	switch r.match {
+	case "x":
+		value = p.x
+	case "m":
+		value = p.m
+	case "a":
+		value = p.a
+	case "s":
+		value = p.s
+	default:
+		return true // default to new queue
+	}
+
+	if r.op == ">" && value > r.value {
+		return true
+	} else if r.op == "<" && value < r.value {
+		return true
+	}
+	return false // no match
+}
+
+func solveWorkflow(parts []part, workflows map[string][]rule) int {
+	// var rejected []part
+	var accepted []part
+
+	for _, p := range parts {
+		workflow := "in"
+
+	nextStep:
+		for workflow != "" {
+			for _, r := range workflows[workflow] {
+				if !r.Match(p) {
+					continue
+				}
+				workflow = r.queue
+
+				if workflow == "A" {
+					accepted = append(accepted, p)
+					workflow = ""
+					break nextStep
+				}
+				if workflow == "R" {
+					// rejected = append(rejected, p)
+					workflow = ""
+					break nextStep
+				}
+
+				continue nextStep
+			}
+		}
+	}
+
+	sum := 0
+	for _, p := range accepted {
+		sum += p.x
+		sum += p.m
+		sum += p.a
+		sum += p.s
+	}
+	return sum
+}
+
+func solveRanges(workflows map[string][]rule) uint {
+
+	pq := aoc.PriorityQueue(func(a, b *queue) bool { return false })
+	pq.Insert(&queue{
+		"in",
+		block{
+			ranger{1, 4000},
+			ranger{1, 4000},
+			ranger{1, 4000},
+			ranger{1, 4000},
+		}})
+
+	var accepted []block
+	// var rejected []block
+
+	for !pq.IsEmpty() {
+		current := pq.ExtractMin()
+		for _, rule := range workflows[current.name] {
+			next := &queue{name: rule.queue, block: current.block}
+
+			switch rule.match {
+			case "x":
+				current.x, next.x = split(current.x, rule.value, rule.op == ">")
+			case "m":
+				current.m, next.m = split(current.m, rule.value, rule.op == ">")
+			case "a":
+				current.a, next.a = split(current.a, rule.value, rule.op == ">")
+			case "s":
+				current.s, next.s = split(current.s, rule.value, rule.op == ">")
+			}
+
+			switch next.name {
+			case "R":
+				// rejected = append(rejected, next.block)
+
+			case "A":
+				accepted = append(accepted, next.block)
+
+			default:
+				pq.Insert(next)
+			}
+		}
+	}
+
+	var sum uint
+	for _, a := range accepted {
+		sum += uint((a.x[1] - a.x[0] + 1) * (a.m[1] - a.m[0] + 1) * (a.a[1] - a.a[0] + 1) * (a.s[1] - a.s[0] + 1))
+	}
+
+	return sum
+}
+
+type ranger [2]int
+type block struct {
+	x, m, a, s ranger
+}
+type queue struct {
+	name string
+	block
+}
+
+func split(a ranger, n int, gt bool) (current ranger, next ranger) {
+	if gt { // x > N => [0,N] [N++,inf]
+		return ranger{a[0], n}, ranger{n + 1, a[1]}
+	}
+
+	// x < N => [N,inf] [0,N--]
+	return ranger{n, a[1]}, ranger{a[0], n - 1}
+}

aoc2023/day19/main_test.go

@@ -25,7 +25,7 @@ func TestExample(t *testing.T) {
 
 	t.Log(result)
 	is.Equal(result.valuePT1, 19114)
-	is.Equal(result.valuePT2, 0)
+	is.Equal(result.valuePT2, uint(167409079868000))
 }
 
 func TestSolution(t *testing.T) {
@@ -37,5 +37,5 @@ func TestSolution(t *testing.T) {
 
 	t.Log(result)
 	is.Equal(result.valuePT1, 377025)
-	is.Equal(result.valuePT2, 0)
+	is.Equal(result.valuePT2, uint(135506683246673))
 }

aoc2023/day20/example1.txt

@@ -0,0 +1,5 @@
+broadcaster -> a, b, c
+%a -> b
+%b -> c
+%c -> inv
+&inv -> a

aoc2023/day20/example2.txt

@@ -0,0 +1,5 @@
+broadcaster -> a
+%a -> inv, con
+&inv -> b
+%b -> con
+&con -> output

aoc2023/day20/input.txt

@@ -0,0 +1,58 @@
+%vg -> lf, vd
+%dr -> kg
+%cn -> mv, pt
+%rq -> bk, gr
+%vp -> lp, bk
+%kg -> lv
+%lv -> jc, tp
+%sj -> rm, vd
+%jc -> tp, qr
+%km -> tp, dr
+%jx -> cn
+&vd -> tf, lf, nb, cx, hx, lr
+%lp -> jt, bk
+%vj -> ps
+broadcaster -> km, lr, xh, rf
+%dj -> pt, gc
+%cg -> vd, hx
+&ln -> tg
+%fl -> pt, sk
+%lm -> tr, bk
+%lr -> vd, vg
+&pt -> vq, rf, cm, jx, rg
+%cx -> gp
+%gp -> vd, sj
+&db -> tg
+%st -> vd
+%jt -> bk
+%jh -> lm, bk
+%xf -> bd, tp
+%gc -> cm, pt
+&tp -> dr, km, kg, db, vj, qr
+%ps -> xf, tp
+%rf -> pt, dj
+%lf -> nb
+%bd -> tp, gg
+%dk -> tp, vj
+%mn -> jh, bk
+&tg -> rx
+%ql -> bk, zx
+%tr -> bk, vp
+%sk -> pt
+%nb -> cg
+%sb -> vd, cx
+%qr -> dk
+%xh -> bk, ql
+%rg -> sd
+%hx -> sb
+%sd -> pt, jx
+%gr -> bk, mn
+%gg -> tp
+%zx -> rq
+&bk -> xh, ln, zx
+%rm -> st, vd
+%hq -> fl, pt
+&vq -> tg
+%cm -> rg
+&tf -> tg
+%mv -> pt, hq

aoc2023/day20/main.go

@@ -0,0 +1,282 @@
+package main
+
+import (
+	"bufio"
+	_ "embed"
+	"fmt"
+	"strings"
+
+	aoc "go.sour.is/advent-of-code"
+	"golang.org/x/exp/maps"
+)
+
+// var log = aoc.Log
+
+func main() { aoc.MustResult(aoc.Runner(run)) }
+
+type result struct {
+	valuePT1 int
+	valuePT2 int
+}
+
+func (r result) String() string { return fmt.Sprintf("%#v", r) }
+
+func run(scan *bufio.Scanner) (*result, error) {
+	m := &machine{}
+	receivers := make(map[string][]string)
+
+	for scan.Scan() {
+		text := scan.Text()
+
+		name, text, _ := strings.Cut(text, " -> ")
+		dest := strings.Split(text, ", ")
+
+		switch {
+		case name == "broadcaster":
+			m.Add(name, &broadcaster{dest: dest})
+		case strings.HasPrefix(name, "%"):
+			name = strings.TrimPrefix(name, "%")
+			m.Add(name, &flipflop{name: name, dest: dest})
+
+		case strings.HasPrefix(name, "&"):
+			name = strings.TrimPrefix(name, "&")
+			m.Add(name, &conjunction{name: name, dest: dest})
+		}
+
+		for _, d := range dest {
+			// rx is present so enable pt 2
+			if d == "rx" {
+				m.Add("rx", &rx{})
+			}
+			receivers[d] = append(receivers[d], name)
+		}
+	}
+
+	m.setup(receivers)
+
+	result := &result{}
+
+	for i := 0; i < 10_000; i++ { // need enough presses to find the best LCM values for each conjunction
+		if i == 1000 {
+			result.valuePT1 = m.highPulses * m.lowPulses
+		}
+		m.Push(i)
+	}
+
+	// rx is present.. perform part 2.
+	if rx, ok := receivers["rx"]; ok {
+		tip := m.m[rx[0]].(*conjunction) // panic if missing!
+
+		var lvalues []int
+		for k, v := range tip.pushes {
+			for i, h := range makeHistory(v) {
+				if i == 1 && len(h) > 0 && h[0] > 0 {
+					fmt.Println(tip.name, k, "frequency", h[0])
+					lvalues = append(lvalues, h[0])
+				}
+			}
+		}
+
+		result.valuePT2 = aoc.LCM(lvalues...)
+		fmt.Println(tip.name, "LCM", result.valuePT2, lvalues)
+	}
+	return result, nil
+}
+
+type signal bool
+
+const (
+	LOW  signal = false
+	HIGH signal = true
+)
+
+type message struct {
+	signal
+	from, to string
+}
+
+type machine struct {
+	m map[string]pulser
+
+	queue []message
+
+	press      int
+	highPulses int
+	lowPulses  int
+}
+
+func (m *machine) Add(name string, p pulser) {
+	if m.m == nil {
+		m.m = make(map[string]pulser)
+	}
+	p.SetMachine(m)
+	m.m[name] = p
+}
+func (m *machine) Send(msgs ...message) {
+	m.queue = append(m.queue, msgs...)
+	for _, msg := range msgs {
+		// fmt.Println(msg)
+		if msg.signal {
+			m.highPulses++
+		} else {
+			m.lowPulses++
+		}
+	}
+}
+func (m *machine) Push(i int) {
+	m.press = i
+	m.Send(generate(LOW, "button", "broadcaster")...)
+	m.processQueue(i)
+}
+func (m *machine) processQueue(i int) {
+	// look for work and process up to the queue length. repeat.
+	hwm := 0
+	for hwm < len(m.queue) {
+		end := len(m.queue)
+
+		for ; hwm < end; hwm++ {
+			msg := m.queue[hwm]
+
+			if p, ok := m.m[msg.to]; ok {
+				// fmt.Println(i, "S:", m.m[msg.from], msg.signal, "R:", p)
+				p.Pulse(msg)
+			}
+		}
+
+		hwm = 0
+		copy(m.queue, m.queue[end:])
+		m.queue = m.queue[:len(m.queue)-end]
+		// fmt.Println("")
+	}
+}
+func (m *machine) setup(receivers map[string][]string) {
+	for name, recv := range receivers {
+		if p, ok := m.m[name]; ok {
+			if p, ok := p.(interface{ Receive(...string) }); ok {
+				p.Receive(recv...)
+			}
+		}
+	}
+}
+
+type pulser interface {
+	Pulse(message)
+	SetMachine(*machine)
+}
+
+// IsModule implements the machine registration for each module.
+type IsModule struct {
+	*machine
+}
+
+func (p *IsModule) SetMachine(m *machine) { p.machine = m }
+
+type broadcaster struct {
+	dest []string
+	IsModule
+}
+
+func (b *broadcaster) Pulse(msg message) {
+	b.Send(generate(msg.signal, "broadcaster", b.dest...)...)
+}
+
+type flipflop struct {
+	name  string
+	state signal
+	dest  []string
+
+	IsModule
+}
+
+func (b *flipflop) Pulse(msg message) {
+	if !msg.signal {
+		b.state = !b.state
+		b.Send(generate(b.state, b.name, b.dest...)...)
+	}
+}
+
+type conjunction struct {
+	name  string
+	state map[string]signal
+	dest  []string
+
+	pushes map[string][]int
+
+	IsModule
+}
+
+func (b *conjunction) Receive(names ...string) {
+	if b.state == nil {
+		b.state = make(map[string]signal)
+		b.pushes = make(map[string][]int)
+	}
+	for _, name := range names {
+		b.state[name] = false
+		b.pushes[name] = []int{}
+	}
+}
+func (b *conjunction) Pulse(msg message) {
+	b.state[msg.from] = msg.signal
+
+	if msg.signal {
+		// collect frequency of pushes to esti,ate rate
+		b.pushes[msg.from] = append(b.pushes[msg.from], b.press)
+	}
+
+	if all(HIGH, maps.Values(b.state)...) {
+		b.Send(generate(LOW, b.name, b.dest...)...)
+		return
+	}
+	b.Send(generate(HIGH, b.name, b.dest...)...)
+}
+
+type rx struct {
+	IsModule
+}
+
+func (rx *rx) Pulse(msg message) {
+	if !msg.signal {
+		panic("pulse received") // will never happen...
+	}
+}
+
+// helper funcs
+func all[T comparable](match T, lis ...T) bool {
+	for _, b := range lis {
+		if b != match {
+			return false
+		}
+	}
+
+	return true
+}
+func generate(t signal, from string, destinations ...string) []message {
+	msgs := make([]message, len(destinations))
+	for i, to := range destinations {
+		msgs[i] = message{signal: t, from: from, to: to}
+	}
+	return msgs
+}
+
+// makeHistory from day 9
+func makeHistory(in []int) [][]int {
+	var history [][]int
+	history = append(history, in)
+
+	// for {
+	var diffs []int
+
+	current := history[len(history)-1]
+
+	for i := range current[1:] {
+		diffs = append(diffs, current[i+1]-current[i])
+	}
+
+	history = append(history, diffs)
+
+	// if len(diffs) == 0 || aoc.Max(diffs[0], diffs[1:]...) == 0 && aoc.Min(diffs[0], diffs[1:]...) == 0 {
+	// 	break
+	// }
+	// }
+	return history
+}

aoc2023/day20/main_test.go

@@ -0,0 +1,56 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"testing"
+
+	_ "embed"
+
+	"github.com/matryer/is"
+)
+
+//go:embed example1.txt
+var example1 []byte
+
+//go:embed example2.txt
+var example2 []byte
+
+//go:embed input.txt
+var input []byte
+
+func TestExample1(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(example1))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 32000000)
+	is.Equal(result.valuePT2, 0)
+}
+
+func TestExample2(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(example2))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 11687500)
+	is.Equal(result.valuePT2, 0)
+}
+
+func TestSolution(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(input))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 819397964)
+	is.Equal(result.valuePT2, 252667369442479)
+}

aoc2023/day21/example.txt

@@ -0,0 +1,11 @@
+...........
+.....###.#.
+.###.##..#.
+..#.#...#..
+....#.#....
+.##..S####.
+.##..#...#.
+.......##..
+.##.#.####.
+.##..##.##.
+...........

aoc2023/day21/input.txt

@@ -0,0 +1,131 @@
+...................................................................................................................................
+.#.......#..#...#.......#......#....#..#...#...#....#.#..........................................#...............#..........#......
+.............##..................#......#.#....#.......................##..#........................#......#..........#............
+......#..........................#....#.....#.............#................##....#.#.............#.........#.##...........#........
+.#................#............................#...........................#..##.....#..................#..##..#.#.........##......
+.....#.............#.....##.............##..........#...........#.............#.....#...........#.#.......#....#......#..........#.
+........#....................#....#.#.#......##........#...........#...........#..........#...#..........#......................#..
+.........#.#...#.......#........#........##...#...#..##........................................##...#.#........................#...
+......#.....#..#..#.#..#..............#...#..#.....#...........#.....#........#.#...........#...........#.#...............#.....#..
+...........#.......####..#.#..............##................#.#.#.....................##.....................#...#..............#..
+......###...#......#................##...#...#....#...........#...#..............#.........#..#..................................#.
+...............#..##..........#...........................##......#.##.........................#..#.#...........#.#...........#....
+...##........#...#...#...##...##...........#..#...................#...................#.#..#.........#.......#..#...........##...#.
+................#.....#..##......#.....#.....##............#..#..........##...........................#.#.......##.....#.....#.....
+.#..#.......#.#...#..##.....#............................#......#...#....#................#.#..#.....#.......##................#...
+...............#.....#........................#..........#.....#..............................................#..................#.
+.....#......#..........................................#....................................#..#.......#.#..#......#.#....#..##....
+............##............#.......###.......................#..#....#......................................#..#.........#..........
+..#...............#.....#...#...#......................#...#.#..............................#.#..#.#.....#.#.#..#....#.....#...##..
+.#.............................##.................#.......#.......##....#....................#.....#.#........#.....#........#.....
+.#....##...................##.....#.#..............#.#....#....#..#....#......#..........#.....##............#....#.............##.
+.........#....#.....#..#.........#....#.#..........#...#...#.......#....#..##.......................#.#..#........#..#....#..#.#...
+..#..................#.......#..#.#..............##.......#........#..............#.........#..#....#......#..#..........#.........
+........#.....#......#.....#......#...#.......#....#.......#.#..#................#....................##.............#.......#.....
+..#.................#..............#...........................................#.....#..................#...#.#..................#.
+.......#......#.....#...........................#.....#..................#.....................#.....#.#......#........#.#.......#.
+..#.#.#...................#...#..#................#....#.......#......................#...............#.........##...#.#.....###...
+.....#...#....##....#........####...........#.................#...#...........................................#..............##....
+..##.#..#.#..........#.#.#..#................................#..#.............#..#......#...........................#.##...........
+..............#.............................##........#..##........................#.............................#........#........
+........#.........#........#..#........#..#........#...#.#........#...........#.........................#.#..........#...#......#..
+.........##.....#........#.....................#..#.............#.....#........#....................#....#.#.#......#.....#........
+......................#...................####..#.........#....#.........#...........#..................#..#.................#.....
+..#.........#...#.....##................##.##....#.....#....#..............................#..#.............#..#...................
+..........##......#..#..............#.#....#......#................#.....#....#..............#..................#..................
+.#.#..####...#....................#.#.#.....#...#...................#....#.#.....#.#.......#.#...........#......#.#................
+.......#.........#..#.#..............###.......#....#.........................#.......#.###...#............#....#.#..#....###.#....
+........#....#...#......#.................#..........................#.........................#...........##.............#.#......
+.#..............#.....................#......#.............##............#..#..........#...................#...#....#..............
+......#..#..#.#...............#........###.......#.#...........#...........#.#.........#..#.....................#......#..#.#......
+.....#...............#.........#....#..........#.......#.......#......#...#..##.....#.....#........#.#.......#.......#..#...#......
+..#............#.....................#...#.......#....###...........#.....#.#.................#................#.........#..##.#...
+..............................#.....#..................................#.....##...............#.......#.........#.....#....##......
+..#...##...#...#..............#.................##..#......#.................#....#......#...#...#......#..........................
+.........#....#..............#........#..#...............#....#...#.....#..#......#.........#.......#.#..#........#...........#....
+........#..#....................#.........#...##.#.#..............#......#.#..........##...##....#......................#..........
+.##..#....#....#.......##......#............#..#......#.....##..................#####..#...#......#.#...#..........#.#.....#..#....
+..#...........#....................#.......#......#.........#...............#......#........##........#.................#.....#.#..
+..#....#.#...............#.#.........................#.............####..............................##................###.........
+.....#.......................................#....#...##...#.......#.......#.....#.##..##.................#.....................##.
+.........#...........#..#..##.#..........#..#.........#..#.....#...................................##....#...............#..#.#....
+.....#..#...........##............#........#..................#............#..........#..........#..#...........#..................
+............................#.........#...............#..................#.#....#.#..#........#.....#...........#...........#......
+................#...##.#....#..##..........#.#........##.#..#..#.....................#....#.................#.#...............#....
+.#.....#..............#.#..........#..#........#...............#..#.#..##..#.#.#.........................#.................#.......
+....#..............#................#.....#..#.......#..#.#.........#..........#..........#.....#..........##.....#............#...
+..............##...........#.......#......#..................#.......#.....#.#...#...............#.#........#......#............#..
+................#.....#....#........#....#.......#.#.##.....#...#..#.##...#................#.#.....#....#.............#............
+...........#.#.##..####.....#....#.#...#.#...........#...#.......................#.#....#.....#..#................###..............
+...................#....#..........#.#..##.....#..#..#......###............#..#...........#....#......#............................
+...........................................#.......#..............#.##.......##.......#...#.....#.#..#.....#..###..................
+............###........#.......#.#....#.....#....#..#........#.........##....#.....#..........#......#............#..#.#...........
+............#..........#................##.#..............#.....#................#....................................#..#.........
+...........#.....#.....................#...#.....#.......#..........#....#.....###.....##.#.##.#.....#......#......#.......#.......
+.....................#..#.....#...##.....#..#...........#....#....##............##.................##............##................
+.................................................................S.................................................................
+........#.#........#..........#.....#......#........#.#............#.#.........##...#............#...#.....#...........#.....#.....
+..................##.......#......#..#..................#..##......#.........#...#.........#............#....#...........##........
+..................#...........#.##.......#..............#....................#.#....#...##...#.....#.......#..#.....##.............
+...........#....#....##...#................................#.........#.................#....#.......................#...#..........
+.............#.#.#.....#.#...#.......#.#...........#....#.#.........#........##......#.......#.......##...#..........#.##..........
+...........##.#....#....#..#.....#...............#......................#...........#.....#...........#.#.......#..................
+.#.......................#.#...##.#....#.#...........#.#....##.##......#........................##....#.#....#.....................
+...#..................#.#...........##....###.................#....................##......#.....#............#.##....#.......##...
+.#..................####...#.#..#.##.#...####...#......#....................#..........................#....#......................
+.....#..........#.....#.#...............#.........##...#......#.#.....#...........#.....#............##......#.....#...............
+......#........#....#..#............................###.#...##........#........#.................#..#........#...............##....
+......................#.........................##....#...#..............#..#............#.#....#......##.#......#.........##......
+..................#....#...#.#.......#..............#..#..#...#.......#...#.....#.....#...............#.#.#...............#........
+...#...##......................##..##...........#......#.............#............#...........##.......#....#......................
+.............................##...........##...#...#.....#....#.......#.#..#.....##...............#..#.#......#..............##....
+...#..#.#...#.......#..................#............#....#.#.##.#.........#......#........#..#..........#....##...........#....#...
+.....#.............................#......#.#.....#.##.#.................#.........#..#..#.#.#........................#.#.......#..
+....#........#........#....#.#.#.....#.##............###.#..........#...##......#........##...#.........#.............#........#...
+..#..............................#.............................#......#...................#...#......#.............#...............
+.......#...#...............#.................##....................#....##.......#....##....##...#..................#..............
+.........................#...#..#.....##.............#...##.......#.....#...#..............#.....#.#.#..#........................#.
+......#.......##.#.............#....................#...#...........#...#..##....#.....#............#...........#........#.........
+...#....#...#......#........................#.....#.........#......#........#.....#.#...........#.#..............#......#....#.....
+........#..........#...................#...........##.#..#...#................#....##.............#................#....#..........
+........#.......#....#.............#..........#...................#.#....#.#........#..#..............................#..........#.
+............#........#....................#.#.........#......#.............#................#...#.............#....#...............
+..#..............................#..#....##.....#......................##...#..#.........#......#......................#...#...#.#.
+.##....#.............#...........##..................#...#..............#.......#................................#.........#.......
+.....#......#.#.....##...........#.....#.......#..........##..#.............#.#.........#.#.#.............##........#......#..#....
+.......#.......#.#.#..#......................#....#............##....#...........#.........................#......#................
+.........##.........#..............#.#.#....#...#.......#.................................#..##..................##.###.##...#.....
+......................#...#.#.......#..#.#..........#........#.......#.................#..................................#........
+....##........#.........#.........................#................#......#...#.....#..................................#..#.#......
+...##..............#..................#...#......#........###..#.......#..........#..............................#......#..........
+.#.#.#....#..........#......#.#.........#.....#...............................#.....#.#............#....#........#.............#...
+........#.........#.........#......................#..#......##.....#..#..........................#......##....#......##.##.....#..
+.##...#.......#.#....#..#.#...................#.........#....#...........#.....#.........#............##......#............#.......
+.##..#.........#..........#.#.................................#.#.#...............................#............#......##...#.#.....
+......#........#..#...#............#..............#............#......##.....#.................................#......#.#.....#....
+..........#........#...........#....................................#.....#...............................#............##....#.##..
+........#.............#..#......##..................#.............#..#...#.#.....#...#...............#........................#....
+....#...............#..........#....#...........................#....##.##...................#.#.......#...#.##....#........##..#..
+......#.....#..#..........###...#.................####.###..........#...........#..........#......#............................#...
+.#...#......#........#..#............##...............#.##......#...#.....#....................#.........#............#...#........
+................##...................#.##..............#...#..#.......#.......###........#..#..#........#...##.....................
+..............#....#..#..#.............##..............#................................#.....#..#....###.##..............#........
+..#..............#........................................#..........#.....#..................#............#..#....................
+.........#...#.....#...#...##...........#.###............##...#........#......................##......#....#.......#...............
+....#....#.....#.......#......................................#.#.#....#..#..#..........#...................#........#...#.........
+..#..#..................#..............#...#..#.........#......#....#.#................##..........#..#................#...........
+...#...................#...........#....#...#.............##...#.......#.#..........#..#...............#....#....#.............#...
+.......................##.#.#..##........#....#.........#.#.#.....##..............#.......#.......##.#..........#.#................
+.....#..#..................#..##....#.......#.............#...#.....#.............#.............#.#...............#.....##......##.
+...#.#.....#..........#.#............#..#..........................##.............#....#.......#.#...#...#....................#.#..
+............##.#............#....#....#....#..##...#...............................#...#...#.........#.......................##.##.
+....#.#...............#...#.......#............#..#...........................#..............#..........#....#...#...#..#...#....#.
+.......#..#..#.#..#......#..........................#...............#.........#...........#................#..#...#................
+...#..#...#.....#.#.......#....................................................#........#..........#.#...#......#..........#.......
+..#...#.......#..#..............#.#...#.....#...#....#............#..........##...#.........##.............#.......................
+...#.............#...#....#...#.....#.#.#..............#..........#........#........##...........#..#.#......................#.....
+.#.......#.................#...............#..........#.....................#.....#............#......##....#.....#...#....###.....
+...##...........#..........#.#........#............#..#.#........................#.....##............#...##.#.......#.##....#......
+...........#........#...........#.......#......#...#.....#............................#........#..#................#...#....##.....
+...##.##.........#.####..#............#..#.....#.......................#......#..........#.#..#.#....##........#....#.....#..#..##.
+...................................................................................................................................

aoc2023/day21/main.go

@@ -0,0 +1,99 @@
+package main
+
+import (
+	"bufio"
+	_ "embed"
+	"fmt"
+
+	aoc "go.sour.is/advent-of-code"
+)
+
+// var log = aoc.Log
+
+func main() { aoc.MustResult(aoc.Runner(runner(64))) }
+
+type result struct {
+	valuePT1 int
+	valuePT2 int
+}
+
+func (r result) String() string { return fmt.Sprintf("%#v", r) }
+
+func runner(rounds int) func(scan *bufio.Scanner) (*result, error) {
+	return func(scan *bufio.Scanner) (*result, error) {
+		var garden garden
+
+		for scan.Scan() {
+			txt := scan.Text()
+			garden.m = append(garden.m, []rune(txt))
+
+			for i, c := range txt {
+				if c == 'S' {
+					garden.start[0] = len(garden.m) - 1
+					garden.start[1] = i
+				}
+			}
+		}
+		garden.Step(rounds)
+		return &result{
+			valuePT1: len(garden.steps[len(garden.steps)-1]),
+		}, nil
+	}
+}
+
+type garden struct {
+	start aoc.Point[int]
+	m     [][]rune
+	steps []aoc.Set[aoc.Point[int]]
+}
+
+func (g *garden) Neighbors(p aoc.Point[int]) []aoc.Point[int] {
+	var neighbors []aoc.Point[int]
+	for _, n := range []aoc.Point[int]{
+		{p[0] - 1, p[1]},
+		{p[0] + 1, p[1]},
+		{p[0], p[1] - 1},
+		{p[0], p[1] + 1},
+	} {
+		if n[0] >= 0 && n[0] < len(g.m) && n[1] >= 0 && n[1] < len(g.m[0]) && g.m[n[0]][n[1]] != '#' {
+			neighbors = append(neighbors, n)
+		}
+	}
+	return neighbors
+}
+
+func (g *garden) Step(n int) {
+	if len(g.steps) == 0 {
+		g.steps = append(g.steps, aoc.NewSet(g.start))
+	}
+
+	for step := range(n) {
+		g.steps = append(g.steps, aoc.NewSet[aoc.Point[int]]())
+		for p := range g.steps[step] {
+			for _, n := range g.Neighbors(p) {
+				g.steps[step+1].Add(n)
+			}
+		}
+	}
+}
+
+func (g garden) String() string {
+	var b []rune
+	for i, line := range g.m {
+		if i == g.start[0] {
+			line[g.start[1]] = 'X'
+		}
+
+		if steps := len(g.steps) - 1; steps > 0 {	
+			for p := range g.steps[len(g.steps)-1] {
+				if p[0] == i {
+					line[p[1]] = 'O'
+				}
+			}
+		}
+
+		b = append(b, line...)
+		b = append(b, '\n')
+	}
+	return string(b)
+}

aoc2023/day21/main_test.go

@@ -0,0 +1,41 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"testing"
+
+	_ "embed"
+
+	"github.com/matryer/is"
+)
+
+//go:embed example.txt
+var example []byte
+
+//go:embed input.txt
+var input []byte
+
+func TestExample(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(example))
+
+	result, err := runner(6)(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 16)
+	is.Equal(result.valuePT2, 0)
+}
+
+func TestSolution(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(input))
+
+	result, err := runner(64)(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 3709)
+	is.Equal(result.valuePT2, 0)
+}

aoc2023/day25/example.txt

@@ -0,0 +1,13 @@
+jqt: rhn xhk nvd
+rsh: frs pzl lsr
+xhk: hfx
+cmg: qnr nvd lhk bvb
+rhn: xhk bvb hfx
+bvb: xhk hfx
+pzl: lsr hfx nvd
+qnr: nvd
+ntq: jqt hfx bvb xhk
+nvd: lhk
+lsr: lhk
+rzs: qnr cmg lsr rsh
+frs: qnr lhk lsr

aoc2023/day25/main.go

@@ -0,0 +1,63 @@
+package main
+
+import (
+	"bufio"
+	_ "embed"
+	"fmt"
+	"iter"
+	"strings"
+
+	aoc "go.sour.is/advent-of-code"
+)
+
+// var log = aoc.Log
+
+func main() { aoc.MustResult(aoc.Runner(run)) }
+
+type result struct {
+	valuePT1 int
+	valuePT2 int
+}
+
+func (r result) String() string { return fmt.Sprintf("%#v", r) }
+
+func run(scan *bufio.Scanner) (*result, error) {
+	g := aoc.Graph[string, int]()
+	var root string
+
+	for scan.Scan() {
+		line := scan.Text()
+		v, lis, ok := strings.Cut(line, ": ")
+		if !ok {
+			continue
+		}
+
+		if root == "" {
+			root = v
+		}	
+
+		for _, l := range strings.Split(lis, " ") {
+			g.AddEdge(v, l, 1)
+			g.AddEdge(l, v, 1)
+
+		}
+	}
+
+	for i, v := range enumerate(g.BFS(root)) {
+		fmt.Println(i, v)
+	}
+
+	return &result{}, nil
+}
+
+func enumerate[T any](vs iter.Seq[T]) iter.Seq2[int, T] {
+	i := 0
+	return func(yield func(int, T) bool) {
+		for v := range vs {
+			if !yield(i, v) {
+				return
+			}
+			i++
+		}
+	}
+}	

aoc2023/day25/main_test.go

@@ -24,7 +24,7 @@ func TestExample(t *testing.T) {
 	is.NoErr(err)
 
 	t.Log(result)
-	is.Equal(result.valuePT1, 102)
+	is.Equal(result.valuePT1, 50)
 	is.Equal(result.valuePT2, 0)
 }
 

aoc2024/day01/example.txt

@@ -0,0 +1,6 @@
+3   4
+4   3
+2   5
+1   3
+3   9
+3   3

aoc2024/day01/main.go

@@ -0,0 +1,86 @@
+package main
+
+import (
+	"bufio"
+	_ "embed"
+	"fmt"
+	"iter"
+	"slices"
+	"sort"
+
+	aoc "go.sour.is/advent-of-code"
+)
+
+// var log = aoc.Log
+
+func main() { aoc.MustResult(aoc.Runner(run)) }
+
+type result struct {
+	valuePT1 int
+	valuePT2 int
+}
+
+func (r result) String() string { return fmt.Sprintf("%#v", r) }
+
+func run(scan *bufio.Scanner) (*result, error) {
+	var (
+		left  []int
+		right []int
+	)
+
+	for scan.Scan() {
+		txt := scan.Text()
+
+		var l, r int
+		_, err := fmt.Sscanf(txt, "%d %d", &l, &r)
+		if err != nil {
+			return nil, err
+		}
+
+		left = append(left, l)
+		right = append(right, r)
+	}
+
+	sort.Ints(left)
+	sort.Ints(right)
+
+	result := &result{}
+
+	result.valuePT1 = aoc.Reduce(func(i int, z pair[int, int], sum int) int {
+		return sum + aoc.ABS(z.L-z.R)
+	}, 0, zip(slices.Values(left), slices.Values(right)))
+
+	rmap := aoc.Reduce(func(i int, z int, m map[int]int) map[int]int {
+		m[z]++
+		return m
+	}, make(map[int]int), slices.Values(right))
+	
+	for _, v := range left {
+		if r, ok := rmap[v]; ok {	
+			result.valuePT2 += v*r
+		}
+	}
+
+	return result, nil
+}
+
+type pair[L, R any] struct {
+	L L
+	R R
+}
+
+func zip[L, R any](l iter.Seq[L], r iter.Seq[R]) iter.Seq[pair[L,R]] {
+	return func(yield func(pair[L, R]) bool) {
+		pullR, stop := iter.Pull(r)
+		defer stop()
+
+		for l := range l {
+			r, _ := pullR()
+
+			if !yield(pair[L, R]{L: l, R: r}) {
+				return
+			}
+		}
+	}
+}
+