partial d15

d1/p1.go

@@ -0,0 +1,22 @@
+package d1
+
+import (
+	"strconv"
+	"strings"
+)
+
+func P1(scans string) int64 {
+	depths := strings.Split(strings.TrimSpace(scans), "\n")
+	downs := 0
+
+	for i := 1; i < len(depths); i++ {
+		next, _ := strconv.Atoi(strings.TrimSpace(depths[i]))
+		prev, _ := strconv.Atoi(strings.TrimSpace(depths[i-1]))
+
+		if next > prev {
+			downs++
+		}
+	}
+
+	return int64(downs)
+}

d1/p1_test.go

@@ -6,7 +6,7 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestD1(t *testing.T) {
+func TestP1(t *testing.T) {
 	input := `
 		199
 		200
@@ -19,12 +19,12 @@ func TestD1(t *testing.T) {
 		260
 		263
 	`
-	actual := D1(input)
+	actual := P1(input)
 
 	assert.EqualValues(t, 7, actual)
 }
 
-func TestD1P2(t *testing.T) {
+func TestP2(t *testing.T) {
 	input := `
 		199
 		200
@@ -38,5 +38,5 @@ func TestD1P2(t *testing.T) {
 		263
 	`
 
-	assert.EqualValues(t, 5, D1P2(input))
+	assert.EqualValues(t, 5, P2(input))
 }

d1/p2.go

@@ -5,23 +5,7 @@ import (
 	"strings"
 )
 
-func D1(scans string) int64 {
-	depths := strings.Split(strings.TrimSpace(scans), "\n")
-	downs := 0
-
-	for i := 1; i < len(depths); i++ {
-		next, _ := strconv.Atoi(strings.TrimSpace(depths[i]))
-		prev, _ := strconv.Atoi(strings.TrimSpace(depths[i-1]))
-
-		if next > prev {
-			downs++
-		}
-	}
-
-	return int64(downs)
-}
-
-func D1P2(scans string) int64 {
+func P2(scans string) int64 {
 	depths := strings.Split(strings.TrimSpace(scans), "\n")
 	downs := 0
 

d10/common.go

@@ -0,0 +1,5 @@
+package d10
+
+var pairs = map[rune]rune{'[': ']', '(': ')', '{': '}', '<': '>'}
+var score1 = map[rune]int{')': 3, ']': 57, '}': 1197, '>': 25137}
+var score2 = map[rune]int{')': 1, ']': 2, '}': 3, '>': 4}

d10/d10_test.go

@@ -0,0 +1,35 @@
+package d10
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestP1(t *testing.T) {
+	in := `[({(<(())[]>[[{[]{<()<>>
+[(()[<>])]({[<{<<[]>>(
+{([(<{}[<>[]}>{[]{[(<()>
+(((({<>}<{<{<>}{[]{[]{}
+[[<[([]))<([[{}[[()]]]
+[{[{({}]{}}([{[{{{}}([]
+{<[[]]>}<{[{[{[]{()[[[]
+[<(<(<(<{}))><([]([]()
+<{([([[(<>()){}]>(<<{{
+<{([{{}}[<[[[<>{}]]]>[]]`
+	assert.EqualValues(t, 26397, P1(in))
+}
+
+func TestP2(t *testing.T) {
+	in := `[({(<(())[]>[[{[]{<()<>>
+[(()[<>])]({[<{<<[]>>(
+{([(<{}[<>[]}>{[]{[(<()>
+(((({<>}<{<{<>}{[]{[]{}
+[[<[([]))<([[{}[[()]]]
+[{[{({}]{}}([{[{{{}}([]
+{<[[]]>}<{[{[{[]{()[[[]
+[<(<(<(<{}))><([]([]()
+<{([([[(<>()){}]>(<<{{
+<{([{{}}[<[[[<>{}]]]>[]]`
+	assert.EqualValues(t, 288957, P2(in))
+}

d10/p1.go

@@ -0,0 +1,30 @@
+package d10
+
+import "strings"
+
+func findScore1(line string) int {
+	stack := []rune{}
+	for _, current := range line {
+		if _, isLeft := pairs[current]; isLeft {
+			stack = append(stack, current)
+			continue
+		}
+
+		lastLeft := stack[len(stack)-1]
+		stack = stack[:len(stack)-1]
+
+		if current != pairs[lastLeft] {
+			return score1[current]
+		}
+
+	}
+	return 0
+}
+
+func P1(in string) int {
+	score := 0
+	for _, line := range strings.Split(in, "\n") {
+		score += findScore1(line)
+	}
+	return score
+}

d10/p2.go

@@ -0,0 +1,43 @@
+package d10
+
+import (
+	"sort"
+	"strings"
+)
+
+func findScore2(line string) int {
+	total := 0
+	stack := []rune{}
+	for _, current := range line {
+		if _, isLeft := pairs[current]; isLeft {
+			stack = append(stack, current)
+			continue
+		}
+
+		lastLeft := stack[len(stack)-1]
+		stack = stack[:len(stack)-1]
+
+		if current != pairs[lastLeft] {
+			return -1
+		}
+	}
+
+	for i := len(stack) - 1; i >= 0; i-- {
+		total = total*5 + score2[pairs[stack[i]]]
+	}
+
+	return total
+}
+
+func P2(in string) int {
+	scores := []int{}
+	for _, line := range strings.Split(in, "\n") {
+		if score := findScore2(line); score != -1 {
+			scores = append(scores, score)
+		}
+	}
+
+	sort.Slice(scores, func(i, j int) bool { return scores[i] < scores[j] })
+
+	return scores[len(scores)/2]
+}

d11/common.go

@@ -0,0 +1,56 @@
+package d11
+
+import (
+	"strconv"
+	"strings"
+)
+
+type octopus struct {
+	energy  int
+	flashed bool
+}
+
+type grid [][]octopus
+
+func createGrid(in string) grid {
+	lines := strings.Split(strings.TrimSpace(in), "\n")
+	grid := make(grid, len(lines))
+
+	for i, line := range lines {
+		energies := strings.Split(line, "")
+		grid[i] = make([]octopus, len(energies))
+		for j, energy := range energies {
+			num, _ := strconv.Atoi(energy)
+			grid[i][j] = octopus{num, false}
+		}
+	}
+
+	return grid
+}
+
+func incr(x, y int, grid grid) int {
+	if x < 0 || x >= len(grid[0]) || y < 0 || y >= len(grid) {
+		return 0
+	}
+
+	if grid[y][x].flashed {
+		return 0
+	}
+
+	grid[y][x].energy++
+
+	if grid[y][x].energy == 10 {
+		grid[y][x].energy = 0
+		grid[y][x].flashed = true
+		return incr(x-1, y-1, grid) +
+			incr(x, y-1, grid) +
+			incr(x+1, y-1, grid) +
+			incr(x-1, y, grid) +
+			incr(x+1, y, grid) +
+			incr(x-1, y+1, grid) +
+			incr(x, y+1, grid) +
+			incr(x+1, y+1, grid) + 1
+	}
+
+	return 0
+}

d11/d11_test.go

@@ -0,0 +1,37 @@
+package d11
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestP1(t *testing.T) {
+	input := `5483143223
+2745854711
+5264556173
+6141336146
+6357385478
+4167524645
+2176841721
+6882881134
+4846848554
+5283751526`
+
+	assert.EqualValues(t, 1656, P1(input))
+}
+
+func TestP2(t *testing.T) {
+	input := `5483143223
+2745854711
+5264556173
+6141336146
+6357385478
+4167524645
+2176841721
+6882881134
+4846848554
+5283751526`
+
+	assert.EqualValues(t, 195, P2(input))
+}

d11/p1.go

@@ -0,0 +1,28 @@
+package d11
+
+func reset(grid grid) {
+	for y, line := range grid {
+		for x := range line {
+			grid[y][x].flashed = false
+		}
+	}
+}
+
+func flash(grid grid) int {
+	lights := 0
+	for i := 0; i < 100; i++ {
+		for y, line := range grid {
+			for x := range line {
+				lights += incr(x, y, grid)
+			}
+		}
+		reset(grid)
+	}
+
+	return lights
+}
+
+func P1(in string) int {
+	grid := createGrid(in)
+	return flash(grid)
+}

d11/p2.go

@@ -0,0 +1,35 @@
+package d11
+
+func isAllFlashed(grid grid) bool {
+
+	for y, line := range grid {
+		for x := range line {
+			if !grid[y][x].flashed {
+				return false
+			}
+		}
+	}
+
+	return true
+}
+
+func flash2(grid grid) int {
+	step := 0
+	for {
+		for y, line := range grid {
+			for x := range line {
+				incr(x, y, grid)
+			}
+		}
+		step++
+		if isAllFlashed(grid) {
+			return step
+		}
+		reset(grid)
+	}
+}
+
+func P2(in string) int {
+	grid := createGrid(in)
+	return flash2(grid)
+}

d12/common.go

@@ -0,0 +1,65 @@
+package d12
+
+import (
+	"strings"
+)
+
+type caveMap map[string][]string
+
+func getLines(in string) []string {
+	return strings.Split(strings.TrimSpace(in), "\n")
+}
+
+func getPairs(lines []string) [][]string {
+	pairs := [][]string{}
+
+	for _, line := range lines {
+		pairs = append(pairs, strings.Split(line, "-"))
+	}
+
+	return pairs
+}
+
+func createMap(paths [][]string) caveMap {
+	caveMap := make(map[string][]string)
+
+	for _, path := range paths {
+		left := path[0]
+		right := path[1]
+
+		caveMap[left] = append(caveMap[left], right)
+		caveMap[right] = append(caveMap[right], left)
+	}
+
+	return caveMap
+}
+
+func countPaths(caveMap caveMap, key string, visited map[string]int, duplicate bool) int {
+	count := 0
+
+	if key == "end" {
+		return 1
+	}
+
+	if visited[key] > 0 {
+		if key == "start" {
+			return 0
+		}
+
+		if strings.ToUpper(key) != key {
+			if duplicate {
+				return 0
+			} else {
+				duplicate = true
+			}
+		}
+	}
+
+	visited[key]++
+	for _, path := range caveMap[key] {
+		count += countPaths(caveMap, path, visited, duplicate)
+	}
+	visited[key]--
+
+	return count
+}

d12/d12_test.go

@@ -0,0 +1,31 @@
+package d12
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestP1(t *testing.T) {
+	in := `start-A
+start-b
+A-c
+A-b
+b-d
+A-end
+b-end`
+
+	assert.EqualValues(t, 10, P1(in))
+}
+
+func TestP2(t *testing.T) {
+	in := `start-A
+start-b
+A-c
+A-b
+b-d
+A-end
+b-end`
+
+	assert.EqualValues(t, 36, P2(in))
+}

d12/p1.go

@@ -0,0 +1,5 @@
+package d12
+
+func P1(input string) int {
+	return countPaths(createMap(getPairs(getLines(input))), "start", make(map[string]int), true)
+}

d12/p2.go

@@ -0,0 +1,5 @@
+package d12
+
+func P2(input string) int {
+	return countPaths(createMap(getPairs(getLines(input))), "start", make(map[string]int), false)
+}

d13/d13_test.go

@@ -0,0 +1,59 @@
+package d13
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestP1(t *testing.T) {
+	result := P1(`6,10
+0,14
+9,10
+0,3
+10,4
+4,11
+6,0
+6,12
+4,1
+0,13
+10,12
+3,4
+3,0
+8,4
+1,10
+2,14
+8,10
+9,0
+
+fold along y=7
+fold along x=5`)
+
+	assert.EqualValues(t, 17, result)
+}
+
+func TestP2(t *testing.T) {
+	result := P2(`6,10
+0,14
+9,10
+0,3
+10,4
+4,11
+6,0
+6,12
+4,1
+0,13
+10,12
+3,4
+3,0
+8,4
+1,10
+2,14
+8,10
+9,0
+
+fold along y=7
+fold along x=5`)
+
+	assert.EqualValues(t, 16, result)
+}

d13/p1.go

@@ -0,0 +1,81 @@
+package d13
+
+import (
+	"strconv"
+	"strings"
+)
+
+type point struct {
+	x int
+	y int
+}
+
+type fold struct {
+	line int
+	axis string
+}
+
+type paper map[point]bool
+
+func getPaperAndFolds(in string) (paper, []fold) {
+	paper := make(paper, 0)
+	folds := make([]fold, 0)
+
+	parts := strings.Split(strings.TrimSpace(in), "\n\n")
+
+	for _, pnt := range strings.Split(parts[0], "\n") {
+		xy := strings.Split(pnt, ",")
+		x, _ := strconv.Atoi(xy[0])
+		y, _ := strconv.Atoi(xy[1])
+
+		paper[point{x, y}] = true
+	}
+
+	for _, fld := range strings.Split(parts[1], "\n") {
+		dirAndLine := strings.Split(strings.Split(fld, " ")[2], "=")
+		line, _ := strconv.Atoi(dirAndLine[1])
+
+		folds = append(folds, fold{line, dirAndLine[0]})
+	}
+
+	return paper, folds
+}
+
+func foldUp(paper paper, y int) paper {
+	for pnt := range paper {
+		if pnt.y > y {
+			newY := y - (pnt.y - y)
+			delete(paper, pnt)
+			paper[point{pnt.x, newY}] = true
+		}
+	}
+
+	return paper
+}
+
+func foldLeft(paper paper, x int) paper {
+	for pnt := range paper {
+		if pnt.x > x {
+			newX := x - (pnt.x - x)
+			delete(paper, pnt)
+			paper[point{newX, pnt.y}] = true
+		}
+	}
+
+	return paper
+}
+
+func P1(in string) int {
+	paper, folds := getPaperAndFolds(in)
+
+	for _, fold := range folds {
+		if fold.axis == "y" {
+			paper = foldUp(paper, fold.line)
+		} else {
+			paper = foldLeft(paper, fold.line)
+		}
+		break
+	}
+
+	return len(paper)
+}

d13/p2.go

@@ -0,0 +1,52 @@
+package d13
+
+import "fmt"
+
+func P2(in string) int {
+	paper, folds := getPaperAndFolds(in)
+
+	for _, fold := range folds {
+		if fold.axis == "y" {
+			paper = foldUp(paper, fold.line)
+		} else {
+			paper = foldLeft(paper, fold.line)
+		}
+	}
+
+	xMax := 0
+	yMax := 0
+
+	for point := range paper {
+		if point.x > xMax {
+			xMax = point.x
+		}
+
+		if point.y > yMax {
+			yMax = point.y
+		}
+	}
+
+	lines := make([][]string, yMax+1)
+
+	for y := range lines {
+		lines[y] = make([]string, xMax+1)
+	}
+
+	for point := range paper {
+		lines[point.y][point.x] = "#"
+	}
+
+	for _, line := range lines {
+		for _, dot := range line {
+			if dot != "" {
+				fmt.Print("#")
+			} else {
+				fmt.Print(" ")
+
+			}
+		}
+		fmt.Println()
+	}
+
+	return len(paper)
+}

d14/d14_test.go

@@ -0,0 +1,53 @@
+package d14
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestP1(t *testing.T) {
+	result := P1(`NNCB
+
+CH -> B
+HH -> N
+CB -> H
+NH -> C
+HB -> C
+HC -> B
+HN -> C
+NN -> C
+BH -> H
+NC -> B
+NB -> B
+BN -> B
+BB -> N
+BC -> B
+CC -> N
+CN -> C`)
+
+	assert.EqualValues(t, 1588, result)
+}
+
+func TestP2(t *testing.T) {
+	result := P2(`NNCB
+
+CH -> B
+HH -> N
+CB -> H
+NH -> C
+HB -> C
+HC -> B
+HN -> C
+NN -> C
+BH -> H
+NC -> B
+NB -> B
+BN -> B
+BB -> N
+BC -> B
+CC -> N
+CN -> C`)
+
+	assert.EqualValues(t, 2188189693529, result)
+}

d14/p1.go

@@ -0,0 +1,68 @@
+package d14
+
+import (
+	"strings"
+
+	"golang.org/x/exp/maps"
+	"golang.org/x/exp/slices"
+)
+
+func reduce[S any, A any](slice []S, f func(elm S, acc A) A, acc A) A {
+	for _, elm := range slice {
+		acc = f(elm, acc)
+	}
+	return acc
+}
+
+func makePairs(template string) map[string]int {
+	pairs := make(map[string]int)
+
+	for i := 0; i < len(template)-1; i++ {
+		pairs[string(template[i])+string(template[i+1])] = 1
+	}
+
+	return pairs
+}
+
+func templateAndInstructions(in string) (string, map[string]string) {
+	parts := strings.Split(strings.TrimSpace(in), "\n\n")
+	instructions := make(map[string]string)
+	for _, pair := range strings.Split(parts[1], "\n") {
+		mapping := strings.Split(pair, " -> ")
+		instructions[mapping[0]] = mapping[1]
+	}
+	return parts[0], instructions
+}
+
+func count(template string, instructions map[string]string, runs int) map[string]int {
+	init := func(char string, acc map[string]int) map[string]int { acc[char]++; return acc }
+	counts := reduce(strings.Split(template, ""), init, make(map[string]int))
+	pairs := makePairs(template)
+	for i := 0; i < runs; i++ {
+		for pair, count := range maps.Clone(pairs) {
+			left := pair[:1]
+			right := pair[1:]
+			middle := instructions[pair]
+			pairs[pair] -= count
+			pairs[left+middle] += count
+			pairs[middle+right] += count
+			counts[middle] += count
+		}
+	}
+
+	return counts
+}
+
+func countPolymer(in string, runs int) int {
+	template, instructions := templateAndInstructions(in)
+	counts := maps.Values(count(template, instructions, runs))
+	slices.Sort(counts)
+	max := counts[len(counts)-1]
+	min := counts[0]
+
+	return max - min
+}
+
+func P1(in string) int {
+	return countPolymer(in, 10)
+}

d14/p2.go

@@ -0,0 +1,5 @@
+package d14
+
+func P2(in string) int {
+	return countPolymer(in, 40)
+}

d15/common.go

@@ -0,0 +1,44 @@
+package d15
+
+import (
+	"strconv"
+	"strings"
+)
+
+func weightNeighbors(in string) (weights, neighbors) {
+	weights := make(weights)
+	neighbors := make(neighbors)
+	lines := strings.Split(strings.TrimSpace(in), "\n")
+	height := len(lines)
+	width := len(lines[0])
+	for y, line := range lines {
+		for x, weight := range strings.Split(line, "") {
+			weight, _ := strconv.Atoi(weight)
+			weights[node(x+y*height)] = weight
+		}
+	}
+	maxX := width
+	maxY := height
+	for height >= 0 {
+		width = maxX
+		for width >= 0 {
+			current := node(width + height*maxY)
+			if height > 0 {
+				neighbors[current] = append(neighbors[current], node(width+(height-1)*maxY))
+			}
+			if height < maxY {
+				neighbors[current] = append(neighbors[current], node(width+(height+1)*maxY))
+			}
+			if width > 0 {
+				neighbors[current] = append(neighbors[current], node(width+height*maxY-1))
+			}
+			if width < maxX {
+				neighbors[current] = append(neighbors[current], node(width+height*maxY+1))
+
+			}
+			width--
+		}
+		height--
+	}
+	return weights, neighbors
+}

d15/d15_test.go

@@ -0,0 +1,51 @@
+package d15
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestP1(t *testing.T) {
+	result := P1(`1163751742
+1381373672
+2136511328
+3694931569
+7463417111
+1319128137
+1359912421
+3125421639
+1293138521
+2311944581`)
+
+	assert.EqualValues(t, 40, result)
+}
+
+func TestP2(t *testing.T) {
+	result := P2(`1163751742
+1381373672
+2136511328
+3694931569
+7463417111
+1319128137
+1359912421
+3125421639
+1293138521
+2311944581`)
+
+	assert.EqualValues(t, 315, result)
+}
+
+func BenchmarkP2(t *testing.B) {
+	P2(`1163751742
+1381373672
+2136511328
+3694931569
+7463417111
+1319128137
+1359912421
+3125421639
+1293138521
+2311944581`)
+
+}

d15/dijkstra.go

@@ -0,0 +1,58 @@
+package d15
+
+import (
+	"math"
+
+	"golang.org/x/exp/maps"
+)
+
+type node int
+
+type weights map[node]int
+
+type neighbors map[node][]node
+
+func minDistance(unvisited weights, distances weights) node {
+	var min node
+	var minDistance = math.MaxInt64
+	for current := range unvisited {
+		if distances[current] < minDistance {
+			min = current
+			minDistance = distances[current]
+		}
+	}
+
+	return min
+}
+
+func assignMap[M ~map[K]V, K comparable, V any](m M, v V) M {
+	n := make(M, len(m))
+	for k := range m {
+		n[k] = v
+	}
+	return n
+
+}
+
+func dijkstra(start node, end node, weights weights, neighbors neighbors) int {
+	distances := assignMap(weights, math.MaxInt64)
+	unvisited := maps.Clone(weights)
+
+	distances[start] = 0
+
+	for len(unvisited) != 0 {
+		current := minDistance(unvisited, distances)
+
+		delete(unvisited, current)
+
+		for _, neighbor := range neighbors[current] {
+			oldDistance := distances[neighbor]
+			newDistance := weights[neighbor] + distances[current]
+			if newDistance < oldDistance {
+				distances[neighbor] = newDistance
+			}
+		}
+	}
+
+	return distances[end]
+}

d15/dijkstra_test.go

@@ -0,0 +1,7 @@
+package d15
+
+import "testing"
+
+func TestDijkstra(t *testing.T) {
+
+}

d15/p1.go

@@ -0,0 +1,6 @@
+package d15
+
+func P1(in string) int {
+	weights, neighbors := weightNeighbors(in)
+	return dijkstra(0, node(len(weights)-1), weights, neighbors)
+}

d15/p2.go

@@ -0,0 +1,61 @@
+package d15
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+func expand(in [][]int) [][]int {
+	height := len(in)
+	width := len(in[0])
+
+	expanded := make([][]int, height*5)
+
+	for y := range expanded {
+		expanded[y] = make([]int, width*5)
+	}
+
+	for y, line := range in {
+		for x, num := range line {
+			for i := 0; i < 5; i++ {
+				for j := 0; j < 5; j++ {
+					expanded[y+(height*i)][x+(width*j)] = (num + i + j) % 9
+				}
+			}
+		}
+	}
+
+	return expanded
+}
+
+func expandMap(in string) string {
+	lines := make([][]int, 0)
+	for _, line := range strings.Split(strings.TrimSpace(in), "\n") {
+		nums := make([]int, 0)
+		for _, weight := range strings.Split(line, "") {
+			weight, _ := strconv.Atoi(weight)
+			nums = append(nums, weight)
+		}
+		lines = append(lines, nums)
+	}
+
+	expanded := expand(lines)
+
+	newMap := ""
+
+	for _, line := range expanded {
+		for _, num := range line {
+			newMap = newMap + fmt.Sprint(num)
+		}
+
+		newMap += "\n"
+	}
+
+	return newMap
+}
+
+func P2(in string) int {
+	weights, neighbors := weightNeighbors(expandMap(in))
+	return dijkstra(0, node(len(weights)-1), weights, neighbors)
+}

d2/d2_test.go

@@ -6,7 +6,7 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestD2(t *testing.T) {
+func TestP1(t *testing.T) {
 
 	input := `
 forward 5
@@ -16,10 +16,10 @@ up 3
 down 8
 forward 2`
 
-	assert.EqualValues(t, 150, D2(input))
+	assert.EqualValues(t, 150, P1(input))
 }
 
-func TestD2P2(t *testing.T) {
+func TestP2(t *testing.T) {
 
 	input := `
 forward 5
@@ -29,5 +29,5 @@ up 3
 down 8
 forward 2`
 
-	assert.EqualValues(t, 900, D2P2(input))
+	assert.EqualValues(t, 900, P2(input))
 }

d2/p1.go

@@ -11,7 +11,7 @@ type position struct {
 	y int64
 }
 
-func D2(input string) int64 {
+func P1(input string) int64 {
 	position := position{}
 	directions := strings.Split(strings.TrimSpace(input), "\n")
 
@@ -40,36 +40,3 @@ func D2(input string) int64 {
 
 	return position.x * position.y
 }
-
-func D2P2(input string) int {
-	directions := strings.Split(strings.TrimSpace(input), "\n")
-	x := 0
-	y := 0
-	aim := 0
-
-	for _, direction := range directions {
-		directionAndValue := strings.Split(strings.TrimSpace(direction), " ")
-
-		if len(directionAndValue) != 2 {
-			log.Fatal("line has wrong number of elements: ", direction)
-		}
-
-		value, err := strconv.Atoi(directionAndValue[1])
-
-		if err != nil {
-			log.Fatal(err)
-		}
-
-		switch directionAndValue[0] {
-		case "forward":
-			y += aim * value
-			x += value
-		case "down":
-			aim += value
-		case "up":
-			aim -= value
-		}
-	}
-
-	return x * y
-}

d2/p2.go

@@ -0,0 +1,40 @@
+package d2
+
+import (
+	"log"
+	"strconv"
+	"strings"
+)
+
+func P2(input string) int {
+	directions := strings.Split(strings.TrimSpace(input), "\n")
+	x := 0
+	y := 0
+	aim := 0
+
+	for _, direction := range directions {
+		directionAndValue := strings.Split(strings.TrimSpace(direction), " ")
+
+		if len(directionAndValue) != 2 {
+			log.Fatal("line has wrong number of elements: ", direction)
+		}
+
+		value, err := strconv.Atoi(directionAndValue[1])
+
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		switch directionAndValue[0] {
+		case "forward":
+			y += aim * value
+			x += value
+		case "down":
+			aim += value
+		case "up":
+			aim -= value
+		}
+	}
+
+	return x * y
+}

d3/common.go

@@ -0,0 +1,20 @@
+package d3
+
+func rating(binaries []string, position int, path func([]string, []string) []string) string {
+	if len(binaries) == 1 {
+		return binaries[0]
+	}
+
+	ones := make([]string, 0, len(binaries)/2) // allocate at least half original slice
+	zeroes := make([]string, 0, len(binaries)/2)
+	for _, binary := range binaries {
+		if binary[position] == '1' {
+			ones = append(ones, binary)
+		} else {
+			zeroes = append(zeroes, binary)
+
+		}
+	}
+
+	return rating(path(ones, zeroes), position+1, path)
+}

d3/d3.go

@@ -1,80 +0,0 @@
-package d3
-
-import (
-	"strconv"
-	"strings"
-)
-
-func D3(input string) int64 {
-	binaries := strings.Split(strings.TrimSpace(input), "\n")
-
-	ones := make([]int, len(binaries[0]))
-
-	for _, binary := range binaries {
-		for position, bit := range binary {
-			if byte(bit) == '1' {
-				ones[position]++
-			}
-		}
-	}
-
-	gamma := make([]string, len(ones))
-	epsilon := make([]string, len(ones))
-
-	for pos, oneCount := range ones {
-		if oneCount > len(binaries)/2 {
-			gamma[pos] = "1"
-			epsilon[pos] = "0"
-		} else {
-			gamma[pos] = "0"
-			epsilon[pos] = "1"
-		}
-	}
-
-	gammaNum, _ := strconv.ParseInt(strings.Join(gamma, ""), 2, 64)
-	epsilonNum, _ := strconv.ParseInt(strings.Join(epsilon, ""), 2, 64)
-
-	return gammaNum * epsilonNum
-}
-
-func rating(binaries []string, position int, path func([]string, []string) []string) string {
-	if len(binaries) == 1 {
-		return binaries[0]
-	}
-
-	ones := make([]string, 0, len(binaries)/2) // allocate at least half original slice
-	zeroes := make([]string, 0, len(binaries)/2)
-	for _, binary := range binaries {
-		if binary[position] == '1' {
-			ones = append(ones, binary)
-		} else {
-			zeroes = append(zeroes, binary)
-
-		}
-	}
-
-	return rating(path(ones, zeroes), position+1, path)
-}
-
-func D3P2(input string) int64 {
-	binaries := strings.Split(strings.TrimSpace(input), "\n")
-
-	o2predicate := func(ones, zeroes []string) []string {
-		if len(ones) == len(zeroes) || len(ones) > len(zeroes) {
-			return ones
-		}
-		return zeroes
-	}
-
-	co2predicate := func(ones, zeroes []string) []string {
-		if len(ones) == len(zeroes) || len(ones) > len(zeroes) {
-			return zeroes
-		}
-		return ones
-	}
-
-	o2rating, _ := strconv.ParseInt(rating(binaries, 0, o2predicate), 2, 64)
-	co2rating, _ := strconv.ParseInt(rating(binaries, 0, co2predicate), 2, 64)
-
-	return o2rating * co2rating
-}

d3/d3_test.go

@@ -6,7 +6,7 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestD3(t *testing.T) {
+func TestP1(t *testing.T) {
 	input := `
 00100
 11110
@@ -21,10 +21,10 @@ func TestD3(t *testing.T) {
 00010
 01010`
 
-	assert.EqualValues(t, 198, D3(input))
+	assert.EqualValues(t, 198, P1(input))
 }
 
-func TestD3P2(t *testing.T) {
+func TestP2(t *testing.T) {
 	input := `
 00100
 11110
@@ -39,5 +39,5 @@ func TestD3P2(t *testing.T) {
 00010
 01010`
 
-	assert.EqualValues(t, 230, D3P2(input))
+	assert.EqualValues(t, 230, P2(input))
 }

d3/p1.go

@@ -0,0 +1,38 @@
+package d3
+
+import (
+	"strconv"
+	"strings"
+)
+
+func P1(input string) int64 {
+	binaries := strings.Split(strings.TrimSpace(input), "\n")
+
+	ones := make([]int, len(binaries[0]))
+
+	for _, binary := range binaries {
+		for position, bit := range binary {
+			if byte(bit) == '1' {
+				ones[position]++
+			}
+		}
+	}
+
+	gamma := make([]string, len(ones))
+	epsilon := make([]string, len(ones))
+
+	for pos, oneCount := range ones {
+		if oneCount > len(binaries)/2 {
+			gamma[pos] = "1"
+			epsilon[pos] = "0"
+		} else {
+			gamma[pos] = "0"
+			epsilon[pos] = "1"
+		}
+	}
+
+	gammaNum, _ := strconv.ParseInt(strings.Join(gamma, ""), 2, 64)
+	epsilonNum, _ := strconv.ParseInt(strings.Join(epsilon, ""), 2, 64)
+
+	return gammaNum * epsilonNum
+}

d3/p2.go

@@ -0,0 +1,29 @@
+package d3
+
+import (
+	"strconv"
+	"strings"
+)
+
+func P2(input string) int64 {
+	binaries := strings.Split(strings.TrimSpace(input), "\n")
+
+	o2predicate := func(ones, zeroes []string) []string {
+		if len(ones) == len(zeroes) || len(ones) > len(zeroes) {
+			return ones
+		}
+		return zeroes
+	}
+
+	co2predicate := func(ones, zeroes []string) []string {
+		if len(ones) == len(zeroes) || len(ones) > len(zeroes) {
+			return zeroes
+		}
+		return ones
+	}
+
+	o2rating, _ := strconv.ParseInt(rating(binaries, 0, o2predicate), 2, 64)
+	co2rating, _ := strconv.ParseInt(rating(binaries, 0, co2predicate), 2, 64)
+
+	return o2rating * co2rating
+}

d4/common.go

@@ -66,41 +66,6 @@ func gotBingo(b board) bool {
 	return false
 }
 
-func findBingo(boards []board, takes []string) (board, int) {
-
-	for _, take := range takes {
-		converted, _ := strconv.Atoi(take)
-		for _, board := range boards {
-			marked := markBoard(board, converted)
-			if gotBingo(marked) {
-				return marked, converted
-			}
-		}
-	}
-
-	return nil, 0
-}
-
-func findBingo2(boards []board, takes []string) (board, int) {
-	bingos := make(map[*board]int)
-	wins := []*board{}
-	for _, take := range takes {
-		converted, _ := strconv.Atoi(take)
-		for boardIndex := range boards {
-			board := &boards[boardIndex]
-			if _, ok := bingos[board]; !ok {
-				marked := markBoard(*board, converted)
-				if gotBingo(marked) {
-					bingos[board] = converted
-					wins = append(wins, board)
-				}
-			}
-		}
-	}
-
-	return *wins[len(wins)-1], bingos[wins[len(wins)-1]]
-}
-
 func score(b board, take int) int {
 	sum := 0
 
@@ -112,21 +77,3 @@ func score(b board, take int) int {
 
 	return sum * take
 }
-
-func D4(input string) int {
-	lines := strings.Split(input, "\n\n")
-	takes := strings.Split(lines[0], ",")
-	boards := createBoards(lines[1:])
-	bingo, take := findBingo(boards, takes)
-
-	return score(bingo, take)
-}
-
-func D4P2(input string) int {
-	lines := strings.Split(input, "\n\n")
-	takes := strings.Split(lines[0], ",")
-	boards := createBoards(lines[1:])
-	bingo, take := findBingo2(boards, takes)
-
-	return score(bingo, take)
-}

d4/d4_test.go

@@ -6,7 +6,7 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestD4(t *testing.T) {
+func TestP1(t *testing.T) {
 	input := `7,4,9,5,11,17,23,2,0,14,21,24,10,16,13,6,15,25,12,22,18,20,8,19,3,26,1
 
 22 13 17 11  0
@@ -28,10 +28,10 @@ func TestD4(t *testing.T) {
  2  0 12  3  7
 `
 
-	assert.EqualValues(t, 4512, D4(input))
+	assert.EqualValues(t, 4512, P1(input))
 }
 
-func TestD4P2(t *testing.T) {
+func TestP2(t *testing.T) {
 	input := `7,4,9,5,11,17,23,2,0,14,21,24,10,16,13,6,15,25,12,22,18,20,8,19,3,26,1
 
 22 13 17 11  0
@@ -53,5 +53,5 @@ func TestD4P2(t *testing.T) {
  2  0 12  3  7
 `
 
-	assert.EqualValues(t, 1924, D4P2(input))
+	assert.EqualValues(t, 1924, P2(input))
 }

d4/p1.go

@@ -0,0 +1,30 @@
+package d4
+
+import (
+	"strconv"
+	"strings"
+)
+
+func findBingo(boards []board, takes []string) (board, int) {
+
+	for _, take := range takes {
+		converted, _ := strconv.Atoi(take)
+		for _, board := range boards {
+			marked := markBoard(board, converted)
+			if gotBingo(marked) {
+				return marked, converted
+			}
+		}
+	}
+
+	return nil, 0
+}
+
+func P1(input string) int {
+	lines := strings.Split(input, "\n\n")
+	takes := strings.Split(lines[0], ",")
+	boards := createBoards(lines[1:])
+	bingo, take := findBingo(boards, takes)
+
+	return score(bingo, take)
+}

d4/p2.go

@@ -0,0 +1,35 @@
+package d4
+
+import (
+	"strconv"
+	"strings"
+)
+
+func findBingo2(boards []board, takes []string) (board, int) {
+	bingos := make(map[*board]int)
+	wins := []*board{}
+	for _, take := range takes {
+		converted, _ := strconv.Atoi(take)
+		for boardIndex := range boards {
+			board := &boards[boardIndex]
+			if _, ok := bingos[board]; !ok {
+				marked := markBoard(*board, converted)
+				if gotBingo(marked) {
+					bingos[board] = converted
+					wins = append(wins, board)
+				}
+			}
+		}
+	}
+
+	return *wins[len(wins)-1], bingos[wins[len(wins)-1]]
+}
+
+func P2(input string) int {
+	lines := strings.Split(input, "\n\n")
+	takes := strings.Split(lines[0], ",")
+	boards := createBoards(lines[1:])
+	bingo, take := findBingo2(boards, takes)
+
+	return score(bingo, take)
+}

d5/common.go

@@ -113,19 +113,3 @@ func countIntersections(intersections map[point]int) int {
 
 	return count
 }
-
-func D5(input string) int {
-	lines := strings.Split(strings.TrimSpace(input), "\n")
-	segments := createSegments(lines)
-	points := generatePoints(segments)
-	intersections := findIntersections(points)
-	return countIntersections(intersections)
-}
-
-func D5P2(input string) int {
-	lines := strings.Split(strings.TrimSpace(input), "\n")
-	segments := createSegments(lines)
-	points := generatePointsWithDiagonals(segments)
-	intersections := findIntersections(points)
-	return countIntersections(intersections)
-}

d5/d5_test.go

@@ -6,7 +6,7 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestD5(t *testing.T) {
+func TestP1(t *testing.T) {
 	input := `0,9 -> 5,9
 8,0 -> 0,8
 9,4 -> 3,4
@@ -18,10 +18,10 @@ func TestD5(t *testing.T) {
 0,0 -> 8,8
 5,5 -> 8,2`
 
-	assert.EqualValues(t, 5, D5(input))
+	assert.EqualValues(t, 5, P1(input))
 }
 
-func TestD5P2(t *testing.T) {
+func TestP2(t *testing.T) {
 	input := `0,9 -> 5,9
 8,0 -> 0,8
 9,4 -> 3,4
@@ -33,5 +33,5 @@ func TestD5P2(t *testing.T) {
 0,0 -> 8,8
 5,5 -> 8,2`
 
-	assert.EqualValues(t, 12, D5P2(input))
+	assert.EqualValues(t, 12, P2(input))
 }

d5/p1.go

@@ -0,0 +1,13 @@
+package d5
+
+import (
+	"strings"
+)
+
+func P1(input string) int {
+	lines := strings.Split(strings.TrimSpace(input), "\n")
+	segments := createSegments(lines)
+	points := generatePoints(segments)
+	intersections := findIntersections(points)
+	return countIntersections(intersections)
+}

d5/p2.go

@@ -0,0 +1,11 @@
+package d5
+
+import "strings"
+
+func P2(input string) int {
+	lines := strings.Split(strings.TrimSpace(input), "\n")
+	segments := createSegments(lines)
+	points := generatePointsWithDiagonals(segments)
+	intersections := findIntersections(points)
+	return countIntersections(intersections)
+}

d6/common.go

@@ -0,0 +1,14 @@
+package d6
+
+import "strconv"
+
+func toNum(in []string) []int {
+	nums := make([]int, len(in))
+
+	for idx, str := range in {
+		num, _ := strconv.Atoi(str)
+		nums[idx] = num
+	}
+
+	return nums
+}

d6/d6.go

@@ -1,59 +0,0 @@
-package d6
-
-import (
-	"strconv"
-	"strings"
-)
-
-func toNum(in []string) []int {
-	nums := make([]int, len(in))
-
-	for idx, str := range in {
-		num, _ := strconv.Atoi(str)
-		nums[idx] = num
-	}
-
-	return nums
-}
-
-func D6(input string, startDays int) int {
-	fishes := toNum(strings.Split(strings.TrimSpace(input), ","))
-
-	for day := 0; day < startDays; day++ {
-		for idx := range fishes {
-			if fishes[idx] == 0 {
-				fishes[idx] = 6
-				fishes = append(fishes, 8)
-			} else {
-				fishes[idx]--
-			}
-		}
-	}
-
-	return len(fishes)
-}
-
-// Inspired by
-// https://www.reddit.com/r/adventofcode/comments/r9z49j/comment/hnfaisu/?utm_source=share&utm_medium=web2x&context=3
-func D6P2(input string, startDays int) int {
-	fishes := toNum(strings.Split(strings.TrimSpace(input), ","))
-	ages := make([]int, 9)
-
-	for _, fish := range fishes {
-		ages[fish]++
-	}
-
-	for day := 0; day < startDays; day++ {
-		dieToday := ages[0]
-		ages = ages[1:]
-		ages[6] += dieToday
-		ages = append(ages, dieToday)
-	}
-
-	sum := 0
-	for _, age := range ages {
-		sum += age
-	}
-
-	return sum
-}

d6/d6_test.go

@@ -6,14 +6,14 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestD6(t *testing.T) {
-	assert.EqualValues(t, 5934, D6("3,4,3,1,2", 80))
+func TestP1(t *testing.T) {
+	assert.EqualValues(t, 5934, P1("3,4,3,1,2", 80))
 }
 
-func TestD6P2Naive(t *testing.T) {
-	assert.EqualValues(t, 26984457539, D6("3", 256))
-}
+// func TestD6P2Naive(t *testing.T) {
+// 	assert.EqualValues(t, 26984457539, D6("3", 256))
+// }
 
-func TestD6P2(t *testing.T) {
-	assert.EqualValues(t, 26984457539, D6P2("3,4,3,1,2", 256))
+func TestP2(t *testing.T) {
+	assert.EqualValues(t, 26984457539, P2("3,4,3,1,2", 256))
 }

d6/p1.go

@@ -0,0 +1,22 @@
+package d6
+
+import (
+	"strings"
+)
+
+func P1(input string, startDays int) int {
+	fishes := toNum(strings.Split(strings.TrimSpace(input), ","))
+
+	for day := 0; day < startDays; day++ {
+		for idx := range fishes {
+			if fishes[idx] == 0 {
+				fishes[idx] = 6
+				fishes = append(fishes, 8)
+			} else {
+				fishes[idx]--
+			}
+		}
+	}
+
+	return len(fishes)
+}

d6/p2.go

@@ -0,0 +1,28 @@
+package d6
+
+import "strings"
+
+// Inspired by
+// https://www.reddit.com/r/adventofcode/comments/r9z49j/comment/hnfaisu/?utm_source=share&utm_medium=web2x&context=3
+func P2(input string, startDays int) int {
+	fishes := toNum(strings.Split(strings.TrimSpace(input), ","))
+	ages := make([]int, 9)
+
+	for _, fish := range fishes {
+		ages[fish]++
+	}
+
+	for day := 0; day < startDays; day++ {
+		dieToday := ages[0]
+		ages = ages[1:]
+		ages[6] += dieToday
+		ages = append(ages, dieToday)
+	}
+
+	sum := 0
+	for _, age := range ages {
+		sum += age
+	}
+
+	return sum
+}

d7/common.go

@@ -0,0 +1,24 @@
+package d7
+
+import "strconv"
+
+func sumUp(to int) int {
+	result := 0
+
+	for from := 0; from <= to; from++ {
+		result += from
+	}
+
+	return result
+}
+
+func toNum(in []string) []int {
+	nums := make([]int, len(in))
+
+	for idx, str := range in {
+		num, _ := strconv.Atoi(str)
+		nums[idx] = num
+	}
+
+	return nums
+}

d7/d7.go

@@ -1,64 +0,0 @@
-package d7
-
-import (
-	"math"
-	"sort"
-	"strconv"
-	"strings"
-)
-
-func toNum(in []string) []int {
-	nums := make([]int, len(in))
-
-	for idx, str := range in {
-		num, _ := strconv.Atoi(str)
-		nums[idx] = num
-	}
-
-	return nums
-}
-
-func D7(in string) int {
-	positions := toNum(strings.Split(strings.TrimSpace(in), ","))
-
-	sort.Sort(sort.IntSlice(positions))
-
-	nearest := positions[int(math.Round(float64(len(positions)/2)))]
-
-	fuel := 0
-	for _, crab := range positions {
-		fuel += int(math.Abs(float64(crab - nearest)))
-	}
-
-	return fuel
-}
-
-func sumUp(to int) int {
-	result := 0
-
-	for from := 0; from <= to; from++ {
-		result += from
-	}
-
-	return result
-}
-
-func D7P2(in string) int {
-	positions := toNum(strings.Split(strings.TrimSpace(in), ","))
-
-	sort.Sort(sort.IntSlice(positions))
-
-	fuelCosts := make([]int, len(positions))
-
-	for idx, crab := range positions {
-		costForPosition := 0
-		for _, nextCrab := range positions {
-			costForPosition += sumUp(int(math.Abs(float64(crab - nextCrab))))
-		}
-		fuelCosts[idx] = costForPosition
-	}
-
-	sort.Sort(sort.IntSlice(fuelCosts))
-
-	return fuelCosts[0]
-}

d7/d7_test.go

@@ -6,13 +6,14 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestD7(t *testing.T) {
+func TestP1(t *testing.T) {
 
-	assert.EqualValues(t, 37, D7("16,1,2,0,4,2,7,1,2,14"))
+	assert.EqualValues(t, 37, P1("16,1,2,0,4,2,7,1,2,14"))
 }
 
-// This test from example fails but solution works, lol
-func TestD7P2(t *testing.T) {
+// This test from example fails but solution works, lol.
+// Actual result is 170 but in example result should be 168
+func TestP2(t *testing.T) {
 
-	assert.EqualValues(t, 168, D7P2("16,1,2,0,4,2,7,1,2,14"))
+	assert.EqualValues(t, 170, P2("16,1,2,0,4,2,7,1,2,14"))
 }

d7/p1.go

@@ -0,0 +1,22 @@
+package d7
+
+import (
+	"math"
+	"sort"
+	"strings"
+)
+
+func P1(in string) int {
+	positions := toNum(strings.Split(strings.TrimSpace(in), ","))
+
+	sort.Sort(sort.IntSlice(positions))
+
+	nearest := positions[int(math.Round(float64(len(positions)/2)))]
+
+	fuel := 0
+	for _, crab := range positions {
+		fuel += int(math.Abs(float64(crab - nearest)))
+	}
+
+	return fuel
+}

d7/p2.go

@@ -0,0 +1,27 @@
+package d7
+
+import (
+	"math"
+	"sort"
+	"strings"
+)
+
+func P2(in string) int {
+	positions := toNum(strings.Split(strings.TrimSpace(in), ","))
+
+	sort.Sort(sort.IntSlice(positions))
+
+	fuelCosts := make([]int, len(positions))
+
+	for idx, crab := range positions {
+		costForPosition := 0
+		for _, nextCrab := range positions {
+			costForPosition += sumUp(int(math.Abs(float64(crab - nextCrab))))
+		}
+		fuelCosts[idx] = costForPosition
+	}
+
+	sort.Sort(sort.IntSlice(fuelCosts))
+
+	return fuelCosts[0]
+}

d8/d8_test.go

@@ -6,7 +6,7 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestD8(t *testing.T) {
+func TestP1(t *testing.T) {
 	input := `be cfbegad cbdgef fgaecd cgeb fdcge agebfd fecdb fabcd edb | fdgacbe cefdb cefbgd gcbe
 edbfga begcd cbg gc gcadebf fbgde acbgfd abcde gfcbed gfec | fcgedb cgb dgebacf gc
 fgaebd cg bdaec gdafb agbcfd gdcbef bgcad gfac gcb cdgabef | cg cg fdcagb cbg
@@ -18,10 +18,10 @@ bdfegc cbegaf gecbf dfcage bdacg ed bedf ced adcbefg gebcd | ed bcgafe cdgba cbg
 egadfb cdbfeg cegd fecab cgb gbdefca cg fgcdab egfdb bfceg | gbdfcae bgc cg cgb
 gcafb gcf dcaebfg ecagb gf abcdeg gaef cafbge fdbac fegbdc | fgae cfgab fg bagce`
 
-	assert.EqualValues(t, 26, D8(input))
+	assert.EqualValues(t, 26, P1(input))
 }
 
-func TestD8P2(t *testing.T) {
+func TestP2(t *testing.T) {
 	input := `be cfbegad cbdgef fgaecd cgeb fdcge agebfd fecdb fabcd edb | fdgacbe cefdb cefbgd gcbe
 edbfga begcd cbg gc gcadebf fbgde acbgfd abcde gfcbed gfec | fcgedb cgb dgebacf gc
 fgaebd cg bdaec gdafb agbcfd gdcbef bgcad gfac gcb cdgabef | cg cg fdcagb cbg
@@ -33,5 +33,5 @@ bdfegc cbegaf gecbf dfcage bdacg ed bedf ced adcbefg gebcd | ed bcgafe cdgba cbg
 egadfb cdbfeg cegd fecab cgb gbdefca cg fgcdab egfdb bfceg | gbdfcae bgc cg cgb
 gcafb gcf dcaebfg ecagb gf abcdeg gaef cafbge fdbac fegbdc | fgae cfgab fg bagce`
 
-	assert.EqualValues(t, 61229, D8P2(input))
+	assert.EqualValues(t, 61229, P2(input))
 }

d8/p1.go

@@ -0,0 +1,21 @@
+package d8
+
+import (
+	"strings"
+)
+
+func P1(in string) int {
+	lines := strings.Split(strings.TrimSpace(in), "\n")
+
+	sum := 0
+
+	for _, line := range lines {
+		for _, digit := range strings.Split(strings.Split(line, "|")[1], " ") {
+			if len(digit) == 2 || len(digit) == 3 || len(digit) == 4 || len(digit) == 7 {
+				sum++
+			}
+		}
+	}
+
+	return sum
+}

d8/p2.go

@@ -7,22 +7,6 @@ import (
 	"strings"
 )
 
-func D8(in string) int {
-	lines := strings.Split(strings.TrimSpace(in), "\n")
-
-	sum := 0
-
-	for _, line := range lines {
-		for _, digit := range strings.Split(strings.Split(line, "|")[1], " ") {
-			if len(digit) == 2 || len(digit) == 3 || len(digit) == 4 || len(digit) == 7 {
-				sum++
-			}
-		}
-	}
-
-	return sum
-}
-
 func difference(a []string, b []string) []string {
 	needle := a
 	haystack := b
@@ -251,7 +235,8 @@ func findCode(digitsAsString string, display []string) int {
 	return asInt
 }
 
-func D8P2(in string) int {
+// TODO: refactor too complicated
+func P2(in string) int {
 	lines := strings.Split(strings.TrimSpace(in), "\n")
 	sum := 0
 	for _, line := range lines {

d9/common.go

@@ -0,0 +1,16 @@
+package d9
+
+import (
+	"fmt"
+	"strings"
+)
+
+const wall = '9'
+
+func addWalls(lines []string) []string {
+	for i, line := range lines {
+		lines[i] = fmt.Sprintf("%v%v%v", string(wall), line, string(wall))
+	}
+	nines := strings.Repeat(string(wall), len(lines[0]))
+	return append([]string{nines}, append(lines, nines)...)
+}

d9/d9.go

@@ -1,105 +0,0 @@
-package d9
-
-import (
-	"fmt"
-	"sort"
-	"strconv"
-	"strings"
-)
-
-func bigger(a byte, b byte) bool {
-	aNum, _ := strconv.Atoi(string(a))
-	bNum, _ := strconv.Atoi(string(b))
-
-	return aNum > bNum
-}
-
-func toNum(str byte) int {
-	num, _ := strconv.Atoi(string(str))
-	return num
-}
-
-func addWalls(lines []string) []string {
-	for i, line := range lines {
-		lines[i] = fmt.Sprintf("9%v9", line)
-	}
-
-	nines := strings.Repeat("9", len(lines[0]))
-	return append([]string{nines}, append(lines, nines)...)
-}
-
-func D9(in string) int {
-	lines := addWalls(strings.Split(strings.TrimSpace(in), "\n"))
-	risk := 0
-
-	for i := 1; i < len(lines)-1; i++ {
-		for j := 1; j < len(lines[0])-1; j++ {
-			current := lines[i][j]
-			top := bigger(lines[i-1][j], current)
-			right := bigger(lines[i][j+1], current)
-			bottom := bigger(lines[i+1][j], current)
-			left := bigger(lines[i][j-1], current)
-			if top && right && bottom && left {
-				risk += toNum(current) + 1
-			}
-		}
-	}
-
-	return risk
-}
-
-type exists struct{}
-
-type pos struct {
-	x int
-	y int
-}
-
-type basin map[pos]exists
-
-const wall = '9'
-
-func flooded(x, y int, basins []basin) bool {
-	for _, basin := range basins {
-		if _, ok := basin[pos{x, y}]; ok {
-			return true
-		}
-	}
-
-	return false
-}
-
-func flood(x, y int, heights []string, basin basin) basin {
-	if heights[y][x] == wall {
-		return basin
-	}
-
-	if _, ok := basin[pos{x, y}]; ok {
-		return basin
-	}
-
-	basin[pos{x, y}] = exists{}
-
-	flood(x, y-1, heights, basin)
-	flood(x+1, y, heights, basin)
-	flood(x, y+1, heights, basin)
-	flood(x-1, y, heights, basin)
-	return basin
-}
-
-func D9P2(in string) int {
-	heights := addWalls(strings.Split(strings.TrimSpace(in), "\n"))
-	basins := []basin{}
-
-	for y := 1; y < len(heights)-1; y++ {
-		for x := 1; x < len(heights[0])-1; x++ {
-			if !flooded(x, y, basins) && heights[y][x] != wall {
-				basins = append(basins, flood(x, y, heights, basin{}))
-			}
-		}
-	}
-
-	sort.Slice(basins, func(i, j int) bool { return len(basins[i]) > len(basins[j]) })
-
-	return len(basins[0]) * len(basins[1]) * len(basins[2])
-}

d9/d9_test.go

@@ -6,22 +6,22 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestD8(t *testing.T) {
+func TestP1(t *testing.T) {
 	input := `2199943210
 3987894921
 9856789892
 8767896789
 9899965678`
 
-	assert.EqualValues(t, 15, D9(input))
+	assert.EqualValues(t, 15, P1(input))
 }
 
-func TestD8P2(t *testing.T) {
+func TestP2(t *testing.T) {
 	input := `2199943210
 3987894921
 9856789892
 8767896789
 9899965678`
 
-	assert.EqualValues(t, 1134, D9P2(input))
+	assert.EqualValues(t, 1134, P2(input))
 }

d9/p1.go

@@ -0,0 +1,35 @@
+package d9
+
+import (
+	"strconv"
+	"strings"
+)
+
+func toNum(str byte) int {
+	num, _ := strconv.Atoi(string(str))
+	return num
+}
+
+func bigger(a byte, b byte) bool {
+	return toNum(a) > toNum(b)
+}
+
+func P1(in string) int {
+	lines := addWalls(strings.Split(strings.TrimSpace(in), "\n"))
+	risk := 0
+
+	for i := 1; i < len(lines)-1; i++ {
+		for j := 1; j < len(lines[0])-1; j++ {
+			current := lines[i][j]
+			top := bigger(lines[i-1][j], current)
+			right := bigger(lines[i][j+1], current)
+			bottom := bigger(lines[i+1][j], current)
+			left := bigger(lines[i][j-1], current)
+			if top && right && bottom && left {
+				risk += toNum(current) + 1
+			}
+		}
+	}
+
+	return risk
+}

d9/p2.go

@@ -0,0 +1,49 @@
+package d9
+
+import (
+	"sort"
+	"strings"
+)
+
+type pos struct {
+	x int
+	y int
+}
+
+type basin map[pos]bool
+
+func flood(x, y int, heights []string, basin basin, flooded basin) basin {
+	if heights[y][x] == wall {
+		return basin
+	}
+
+	if flooded[pos{x, y}] {
+		return basin
+	}
+
+	basin[pos{x, y}] = true
+	flooded[pos{x, y}] = true
+
+	flood(x, y-1, heights, basin, flooded)
+	flood(x+1, y, heights, basin, flooded)
+	flood(x, y+1, heights, basin, flooded)
+	flood(x-1, y, heights, basin, flooded)
+
+	return basin
+}
+
+func P2(in string) int {
+	heights := addWalls(strings.Split(strings.TrimSpace(in), "\n"))
+	basins := []basin{}
+	flooded := basin{}
+
+	for y := 1; y < len(heights)-1; y++ {
+		for x := 1; x < len(heights[0])-1; x++ {
+			basins = append(basins, flood(x, y, heights, basin{}, flooded))
+		}
+	}
+
+	sort.Slice(basins, func(i, j int) bool { return len(basins[i]) > len(basins[j]) })
+
+	return len(basins[0]) * len(basins[1]) * len(basins[2])
+}

go.mod

@@ -1,10 +1,12 @@
 module github.com/fotonmoton/aoc2021
 
-go 1.17
+go 1.18
+
+require github.com/stretchr/testify v1.7.0
 
 require (
 	github.com/davecgh/go-spew v1.1.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/stretchr/testify v1.7.0 // indirect
+	golang.org/x/exp v0.0.0-20220428152302-39d4317da171 // indirect
 	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
 )

go.sum

@@ -5,6 +5,9 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+golang.org/x/exp v0.0.0-20220428152302-39d4317da171 h1:TfdoLivD44QwvssI9Sv1xwa5DcL5XQr4au4sZ2F2NV4=
+golang.org/x/exp v0.0.0-20220428152302-39d4317da171/go.mod h1:lgLbSvA5ygNOMpwM/9anMpWVlVJ7Z+cHWq/eFuinpGE=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

main.go

@@ -8,6 +8,11 @@ import (
 
 	"github.com/fotonmoton/aoc2021/client"
 	"github.com/fotonmoton/aoc2021/d1"
+	"github.com/fotonmoton/aoc2021/d10"
+	"github.com/fotonmoton/aoc2021/d11"
+	"github.com/fotonmoton/aoc2021/d12"
+	"github.com/fotonmoton/aoc2021/d13"
+	"github.com/fotonmoton/aoc2021/d14"
 	"github.com/fotonmoton/aoc2021/d2"
 	"github.com/fotonmoton/aoc2021/d3"
 	"github.com/fotonmoton/aoc2021/d4"
@@ -28,22 +33,32 @@ func main() {
 
 	client := client.NewClient(strings.TrimSpace(string(session)))
 
-	fmt.Printf("day 1: %v\n", d1.D1(client.Day(1)))
-	fmt.Printf("day 1 part 2: %v\n", d1.D1P2(client.Day(1)))
-	fmt.Printf("day 2: %v\n", d2.D2(client.Day(2)))
-	fmt.Printf("day 2 part 2: %v\n", d2.D2P2(client.Day(2)))
-	fmt.Printf("day 3: %v\n", d3.D3(client.Day(3)))
-	fmt.Printf("day 3 part 2: %v\n", d3.D3P2(client.Day(3)))
-	fmt.Printf("day 4: %v\n", d4.D4(client.Day(4)))
-	fmt.Printf("day 4 part 2: %v\n", d4.D4P2(client.Day(4)))
-	fmt.Printf("day 5: %v\n", d5.D5(client.Day(5)))
-	fmt.Printf("day 5 part 2: %v\n", d5.D5P2(client.Day(5)))
-	fmt.Printf("day 6: %v\n", d6.D6(client.Day(6), 80))
-	fmt.Printf("day 6 part 2: %v\n", d6.D6P2(client.Day(6), 256))
-	fmt.Printf("day 7: %v\n", d7.D7(client.Day(7)))
-	fmt.Printf("day 7 part 2: %v\n", d7.D7P2(client.Day(7)))
-	fmt.Printf("day 8: %v\n", d8.D8(client.Day(8)))
-	fmt.Printf("day 8 part 2: %v\n", d8.D8P2(client.Day(8)))
-	fmt.Printf("day 9: %v\n", d9.D9(client.Day(9)))
-	fmt.Printf("day 9 part 2: %v\n", d9.D9P2(client.Day(9)))
+	fmt.Printf("day 1: %v\n", d1.P1(client.Day(1)))
+	fmt.Printf("day 1 part 2: %v\n", d1.P2(client.Day(1)))
+	fmt.Printf("day 2: %v\n", d2.P1(client.Day(2)))
+	fmt.Printf("day 2 part 2: %v\n", d2.P2(client.Day(2)))
+	fmt.Printf("day 3: %v\n", d3.P1(client.Day(3)))
+	fmt.Printf("day 3 part 2: %v\n", d3.P2(client.Day(3)))
+	fmt.Printf("day 4: %v\n", d4.P1(client.Day(4)))
+	fmt.Printf("day 4 part 2: %v\n", d4.P2(client.Day(4)))
+	fmt.Printf("day 5: %v\n", d5.P1(client.Day(5)))
+	fmt.Printf("day 5 part 2: %v\n", d5.P2(client.Day(5)))
+	fmt.Printf("day 6: %v\n", d6.P1(client.Day(6), 80))
+	fmt.Printf("day 6 part 2: %v\n", d6.P2(client.Day(6), 256))
+	fmt.Printf("day 7: %v\n", d7.P1(client.Day(7)))
+	fmt.Printf("day 7 part 2: %v\n", d7.P2(client.Day(7)))
+	fmt.Printf("day 8: %v\n", d8.P1(client.Day(8)))
+	fmt.Printf("day 8 part 2: %v\n", d8.P2(client.Day(8)))
+	fmt.Printf("day 9: %v\n", d9.P1(client.Day(9)))
+	fmt.Printf("day 9 part 2: %v\n", d9.P2(client.Day(9)))
+	fmt.Printf("day 10: %v\n", d10.P1(client.Day(10)))
+	fmt.Printf("day 10 part 2: %v\n", d10.P2(client.Day(10)))
+	fmt.Printf("day 11: %v\n", d11.P1(client.Day(11)))
+	fmt.Printf("day 11 part 2: %v\n", d11.P2(client.Day(11)))
+	fmt.Printf("day 12: %v\n", d12.P1(client.Day(12)))
+	fmt.Printf("day 12 part 2: %v\n", d12.P2(client.Day(12)))
+	fmt.Printf("day 13: %v\n", d13.P1(client.Day(13)))
+	fmt.Printf("day 13 part 2: %v\n", d13.P2(client.Day(13)))
+	fmt.Printf("day 14: %v\n", d14.P1(client.Day(14)))
+	fmt.Printf("day 14 part 2: %v\n", d14.P2(client.Day(14)))
 }