chore: save hacker rank

README.md.sig

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

aoc_test.go

@@ -9,66 +9,6 @@ import (
 	aoc "go.sour.is/advent-of-code"
 )
 
-func TestReverse(t *testing.T) {
-	is := is.New(t)
-
-	is.Equal(aoc.Reverse([]int{1, 2, 3, 4}), []int{4, 3, 2, 1})
-}
-
-func TestLCM(t *testing.T) {
-	is := is.New(t)
-
-	is.Equal(aoc.LCM([]int{}...), 0)
-	is.Equal(aoc.LCM(5), 5)
-	is.Equal(aoc.LCM(5, 3), 15)
-	is.Equal(aoc.LCM(5, 3, 2), 30)
-}
-
-func TestReadStringToInts(t *testing.T) {
-	is := is.New(t)
-
-	is.Equal(aoc.ReadStringToInts([]string{"1", "2", "3"}), []int{1, 2, 3})
-}
-
-func TestRepeat(t *testing.T) {
-	is := is.New(t)
-
-	is.Equal(aoc.Repeat(5, 3), []int{5, 5, 5})
-}
-
-func TestPower2(t *testing.T) {
-	is := is.New(t)
-
-	is.Equal(aoc.Power2(0), 1)
-	is.Equal(aoc.Power2(1), 2)
-	is.Equal(aoc.Power2(2), 4)
-}
-
-func TestABS(t *testing.T) {
-	is := is.New(t)
-
-	is.Equal(aoc.ABS(1), 1)
-	is.Equal(aoc.ABS(0), 0)
-	is.Equal(aoc.ABS(-1), 1)
-}
-
-func TestTranspose(t *testing.T) {
-	is := is.New(t)
-
-	is.Equal(
-		aoc.Transpose(
-			[][]int{
-				{1, 1},
-				{0, 0},
-				{1, 1},
-			},
-		),
-		[][]int{
-			{1, 0, 1},
-			{1, 0, 1},
-		},
-	)
-}
 
 func TestList(t *testing.T) {
 	is := is.New(t)
@@ -116,23 +56,6 @@ func TestPriorityQueue(t *testing.T) {
 	is.True(v == nil)
 }
 
-func TestSet(t *testing.T) {
-	is := is.New(t)
-
-	s := aoc.Set(1, 2, 3)
-	is.True(!s.Has(0))
-	is.True(s.Has(1))
-	is.True(s.Has(2))
-	is.True(s.Has(3))
-	is.True(!s.Has(4))
-
-	s.Add(4)
-	is.True(s.Has(4))
-
-	items := s.Items()
-	sort.Ints(items)
-	is.Equal(items, []int{1, 2, 3, 4})
-}
 
 func ExamplePriorityQueue() {
 	type memo struct {
@@ -194,26 +117,6 @@ func ExamplePriorityQueue() {
 	// point 5 is 22 steps away.
 	// point 6 is 19 steps away.
 }
-
-func TestStack(t *testing.T) {
-	is := is.New(t)
-
-	s := aoc.Stack(1, 2, 3, 4)
-	is.True(!s.IsEmpty())
-	is.Equal(s.Pop(), 4)
-	is.Equal(s.Pop(), 3)
-	is.Equal(s.Pop(), 2)
-	is.Equal(s.Pop(), 1)
-	is.True(s.IsEmpty())
-	s.Push(4, 3, 2, 1)
-	is.True(!s.IsEmpty())
-	is.Equal(s.Pop(), 1)
-	is.Equal(s.Pop(), 2)
-	is.Equal(s.Pop(), 3)
-	is.Equal(s.Pop(), 4)
-	is.True(s.IsEmpty())
-}
-
 func TestGraph(t *testing.T) {
 	is := is.New(t)
 

go.mod

@@ -1,8 +1,6 @@
 module go.sour.is/advent-of-code
 
-go 1.21.4
-
-toolchain go1.21.5
+go 1.22.0
 
 require (
 	github.com/matryer/is v1.4.1

grids.go

@@ -2,7 +2,11 @@ package aoc
 
 import (
 	"cmp"
+	"fmt"
 	"sort"
+	"strings"
+
+	"golang.org/x/exp/maps"
 )
 
 type Vector struct {
@@ -82,6 +86,76 @@ func (m *Map[I, T]) Valid(p Point[I]) bool {
 	return p[0] >= 0 && p[0] < rows && p[1] >= 0 && p[1] < cols
 }
 
+type cmap[C number, N comparable] struct {
+	base      pather[C, N]
+	neighbors map[N]map[N]C
+}
+
+func (m *cmap[C, N]) Cost(a, b N) C {
+	if v, ok := m.neighbors[a]; ok {
+		return v[b]
+	}
+	return 0
+}
+func (m *cmap[C, N]) Neighbors(n N) []N {
+	if v, ok := m.neighbors[n]; ok {
+		return maps.Keys(v)
+	}
+	return nil
+}
+func (m *cmap[C, N]) Target(n N, c C) bool {
+	return m.base.Target(n, c)
+}
+func (m *cmap[C, N]) String() string {
+	var b = &strings.Builder{}
+
+	for k, nbs := range m.neighbors {
+		fmt.Fprintln(b, k)
+		for to, c := range nbs {
+			fmt.Fprintln(b, "  ", to, c)
+		}
+	}
+
+	return b.String()
+}
+
+func CompressMap[C number, N comparable](p pather[C, N], start N) pather[C, N] {
+	var next = []N{start}
+	var visited = make(map[N]map[N]C)
+
+	var n N
+	for len(next) > 0 {
+		n, next = next[len(next)-1], next[:len(next)-1]
+
+		if _, ok := visited[n]; ok {
+			continue
+		}
+
+		nbs := p.Neighbors(n)
+		if len(nbs) == 2 {
+			a, b := nbs[0], nbs[1]
+			if to, ok := visited[a]; ok {
+				to[b] = to[n] + p.Cost(n, b)
+				delete(to, n)
+				visited[a] = to
+			} else if to, ok := visited[b]; ok {
+				to[a] = to[n] + p.Cost(n, a)
+				delete(to, n)
+				visited[b] = to
+			}
+			continue
+		}
+
+		visited[n] = make(map[N]C)
+		next = append(next, nbs...)
+		for _, to := range nbs {
+			visited[n][to] = p.Cost(n, to)
+		}
+	}
+
+	return &cmap[C, N]{base: p, neighbors: visited}
+}
+
 type adjacencyList[V any, C comparable] map[C][]V
 type graph[V any, W cmp.Ordered, C comparable] map[C]*vertex[V, W]
 type graphOption[V any, W cmp.Ordered, C comparable] func(g *graph[V, W, C])
@@ -117,7 +191,7 @@ func Graph[V any, W cmp.Ordered, C comparable](opts ...graphOption[V, W, C]) *gr
 	return &g
 }
 func (g *graph[V, W, C]) AddVertex(id C, value V) {
-	(*g)[id] = &vertex[V,W]{Value: value}
+	(*g)[id] = &vertex[V, W]{Value: value}
 }
 func (g *graph[V, W, C]) AddEdge(from, to C, w W) {
 	if g == nil {
@@ -130,7 +204,7 @@ func (g *graph[V, W, C]) AddEdge(from, to C, w W) {
 		return
 	}
 
-	(*g)[from].Edges = append((*g)[from].Edges, edge[V,W]{(*g)[to], w})
+	(*g)[from].Edges = append((*g)[from].Edges, edge[V, W]{(*g)[to], w})
 }
 func (g *graph[V, W, C]) Neighbors(v C) []V {
 	if g == nil {
@@ -170,5 +244,3 @@ func WithAdjacencyList[W cmp.Ordered, C comparable](list adjacencyList[C, C]) gr
 		}
 	}
 }
-
-// func GraphFromMap()

hacker01/hacker.go

@@ -0,0 +1,69 @@
+package main
+
+import "fmt"
+import "os"
+import "bufio"
+import "strconv"
+import "strings"
+
+
+var input1 = strings.NewReader(`
+6
+1 2 5 3 6 4
+`)
+
+var input2 = strings.NewReader(`
+15
+1 14 3 7 4 5 15 6 13 10 11 2 12 8 9
+`)
+
+var input3 = os.Stdin
+
+func main() {
+	var length int
+    var tree *node
+    
+    scanner := bufio.NewScanner(input1)
+    for scanner.Scan() {
+		if length == 0 {
+			length, _ = strconv.Atoi(scanner.Text())
+			continue
+		}
+
+        for _, txt := range strings.Fields(scanner.Text()) {		
+			if v, err := strconv.Atoi(txt); err == nil {
+                tree = insert(tree, &node{value: v})
+            }
+        }
+    }
+
+    foo(input{1, "hi"})
+    
+    fmt.Println(tree)
+}
+
+type node struct {
+    value int
+    left *node
+    right *node
+}
+
+func insert(root, n *node) *node {
+        if root == nil {
+            return n
+        }
+        if root.value > n.value {
+            root.left = insert(root.left, n)
+            return root
+        }
+        root.right = insert(root.right, n)
+        return root
+}
+
+func (n *node) String() string {
+    if n == nil { return "" }
+    return fmt.Sprintf("%v %v%v", n.value, n.left.String(), n.right.String())
+}
+
+type input struct{a int; b string}
+func foo (in input) {}

hacker02/hacker.go

@@ -0,0 +1,109 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+
+	aoc "go.sour.is/advent-of-code"
+)
+
+/*
+ * Complete the 'cookies' function below.
+ *
+ * The function is expected to return an INTEGER.
+ * The function accepts following parameters:
+ *  1. INTEGER k
+ *  2. INTEGER_ARRAY A
+ */
+
+func cookies(k int32, A []int32) int32 {
+	var i int32
+	// fmt.Println(" ", A)
+	// sort.Slice(A, func(i, j int) bool { return A[j] < A[i]})
+	// for A[len(A)-1] < k {
+	//     if len(A) < 2 {
+	//         return -1
+	//     }
+	//     // fmt.Println(" ", A[len(A)-1], " + 2x", A[len(A)-2], 2*A[len(A)-2] + A[len(A)-1])
+	//     A[len(A)-2] = 2*A[len(A)-2] + A[len(A)-1]
+	//     A = A[:len(A)-1]
+
+	//     for j:=len(A)-1; j>0 && A[j] > A[j-1]; j-- {
+	//         A[j], A[j-1] = A[j-1], A[j]
+	//     }
+	//     i++
+	//     fmt.Println("A", len(A), i)
+	// }
+
+	pq := aoc.FibHeap(func(a, b *int32) bool { return *a < *b })
+	for i := range A {
+		pq.Insert(&A[i])
+	}
+	for !pq.IsEmpty() && *pq.GetMin() < k {
+		first := *pq.ExtractMin()
+		second := *pq.ExtractMin()
+		third := first + 2*second
+
+		pq.Insert(&third)
+		i++
+	}
+
+	return i
+}
+
+func main() {
+	reader := bufio.NewReaderSize(os.Stdin, 16*1024*1024)
+
+	stdout, err := os.Create("/dev/stderr")
+	checkError(err)
+
+	defer stdout.Close()
+
+	writer := bufio.NewWriterSize(stdout, 16*1024*1024)
+
+	firstMultipleInput := strings.Split(strings.TrimSpace(readLine(reader)), " ")
+
+	nTemp, err := strconv.ParseInt(firstMultipleInput[0], 10, 64)
+	checkError(err)
+	n := int32(nTemp)
+
+	kTemp, err := strconv.ParseInt(firstMultipleInput[1], 10, 64)
+	checkError(err)
+	k := int32(kTemp)
+
+	ATemp := strings.Split(strings.TrimSpace(readLine(reader)), " ")
+
+	var A []int32
+
+	for i := 0; i < int(n); i++ {
+		AItemTemp, err := strconv.ParseInt(ATemp[i], 10, 64)
+		checkError(err)
+		AItem := int32(AItemTemp)
+		A = append(A, AItem)
+	}
+
+	result := cookies(k, A)
+
+	fmt.Fprintf(writer, "%d\n", result)
+
+	writer.Flush()
+}
+
+func readLine(reader *bufio.Reader) string {
+	str, _, err := reader.ReadLine()
+	if err == io.EOF {
+		return ""
+	}
+
+	return strings.TrimRight(string(str), "\r\n")
+}
+
+func checkError(err error) {
+	if err != nil {
+		panic(err)
+	}
+}

hacker02/other.txt

@@ -0,0 +1,2 @@
+8 90
+13 47 74 12 89 74 18 38

itertools_test.go

@@ -0,0 +1,44 @@
+package aoc_test
+
+import (
+	"testing"
+
+	"github.com/matryer/is"
+	aoc "go.sour.is/advent-of-code"
+)
+
+func TestReverse(t *testing.T) {
+	is := is.New(t)
+
+	is.Equal(aoc.Reverse([]int{1, 2, 3, 4}), []int{4, 3, 2, 1})
+}
+
+func TestReadStringToInts(t *testing.T) {
+	is := is.New(t)
+
+	is.Equal(aoc.ReadStringToInts([]string{"1", "2", "3"}), []int{1, 2, 3})
+}
+
+func TestRepeat(t *testing.T) {
+	is := is.New(t)
+
+	is.Equal(aoc.Repeat(5, 3), []int{5, 5, 5})
+}
+
+func TestTranspose(t *testing.T) {
+	is := is.New(t)
+
+	is.Equal(
+		aoc.Transpose(
+			[][]int{
+				{1, 1},
+				{0, 0},
+				{1, 1},
+			},
+		),
+		[][]int{
+			{1, 0, 1},
+			{1, 0, 1},
+		},
+	)
+}

math_test.go

@@ -0,0 +1,33 @@
+package aoc_test
+
+import (
+	"testing"
+
+	"github.com/matryer/is"
+	aoc "go.sour.is/advent-of-code"
+)
+
+func TestLCM(t *testing.T) {
+	is := is.New(t)
+
+	is.Equal(aoc.LCM([]int{}...), 0)
+	is.Equal(aoc.LCM(5), 5)
+	is.Equal(aoc.LCM(5, 3), 15)
+	is.Equal(aoc.LCM(5, 3, 2), 30)
+}
+
+func TestPower2(t *testing.T) {
+	is := is.New(t)
+
+	is.Equal(aoc.Power2(0), 1)
+	is.Equal(aoc.Power2(1), 2)
+	is.Equal(aoc.Power2(2), 4)
+}
+
+func TestABS(t *testing.T) {
+	is := is.New(t)
+
+	is.Equal(aoc.ABS(1), 1)
+	is.Equal(aoc.ABS(0), 0)
+	is.Equal(aoc.ABS(-1), 1)
+}

ranger/channel.go

@@ -0,0 +1,15 @@
+package main
+
+
+func countChan(n int) <-chan int {
+	ch := make(chan int)
+
+	go func() {
+		for i := range n {
+			ch <- i
+		}
+		close(ch)
+	}()
+
+	return ch
+}

ranger/range.go

@@ -0,0 +1,84 @@
+package main
+
+// export GOEXPERIMENT=rangefunc
+import "iter"
+
+func Step(start, stop, step int) iter.Seq[int] {
+	if step < 0 {
+		return func(yield func(int) bool) {
+			for i := start; i <= start && i > stop; i += step {
+				next := yield(i)
+				if !next {
+					return
+				}
+			}
+		}
+	}
+
+	if step > 0 {
+		return func(yield func(int) bool) {
+			for i := start; i >= start && i < stop; i += step {
+				next := yield(i)
+				if !next {
+					println("stopped!")
+					return
+				}
+			}
+		}
+	}
+
+	return func(yield func(int) bool) { yield(start) }
+}
+
+func Fib() iter.Seq[uint] {
+	return func(yield func(uint) bool) {
+		previous, value := uint(1), uint(1)
+		next := yield(value)
+		for next {
+			next = yield(value)
+			value, previous = value+previous, value
+			if value < previous {
+				return
+			}
+		}
+	}
+}
+
+func Fizzbuzzed[T int | uint](from iter.Seq[T]) iter.Seq2[T, string] {
+	pull, stop := iter.Pull(from)
+	return func(yield func(T, string) bool) {
+		defer stop()
+		for {
+			var fizzbuzz string
+			p, ok := pull()
+			if !ok {
+				return
+			}
+			if p%3 == 0 {
+				fizzbuzz = "fizz"
+			}
+			if p%5 == 0 {
+				fizzbuzz += "buzz"
+			}
+			if !yield(p, fizzbuzz) {
+				return
+			}
+		}
+	}
+}
+
+// func main() {
+// 	for i, v := range Fizzbuzzed(Fib()) {
+// 		println(i, v)
+// 	}
+// }
+
+func countScan(n int) (func() bool, func() int) {
+	pos := -1
+	return func() bool {
+			pos++
+			return pos < n
+		}, func() int {
+			return pos
+		}
+}

ranger/range_test.go

@@ -0,0 +1,193 @@
+package main_test
+
+import (
+	"testing"
+
+	"github.com/matryer/is"
+)
+
+// func BenchmarkChan(b *testing.B) {
+// 	sum := 0
+
+// 	for n := range countChan(b.N) {
+// 		sum += n
+// 	}
+// 	b.StopTimer()
+// 	b.Log(sum)
+// }
+
+// func BenchmarkScan(b *testing.B) {
+// 	sum := 0
+// 	scan, value := countScan(b.N)
+// 	for scan() {
+// 		sum += value()
+// 	}
+// 	b.StopTimer()
+// 	b.Log(sum)
+// }
+
+// func BenchmarkRange(b *testing.B) {
+// 	sum := 0
+// 	for n := range countRF(b.N) {
+// 		sum += n
+// 	}
+// 	b.StopTimer()
+// 	b.Log(sum)
+// }
+
+// func TestRangeS(t *testing.T) {
+// 	for i := range Step(0, 10, 3) {
+// 		t.Log(i)
+// 	}
+
+// 	for i := range Step(10, 0, -3) {
+// 		t.Log(i)
+// 	}
+// }
+
+func TestSelect(t *testing.T) {
+	done1 := make(chan struct{})
+	done2 := make(chan struct{})
+
+	go func() {
+		close(done1)
+		close(done2)
+	}()
+
+	for i, ch := range []chan struct{}{done1, done2} {
+		<-ch
+		println("closed", i)
+	}
+}
+
+func TestGCD(t *testing.T) {
+	is := is.New(t)
+	is.Equal(gcdOfStrings("ABAB", "ABABAB"), "AB")
+	is.Equal(gcdOfStrings("ABAB", "ABABABAB"), "ABAB")
+	is.Equal(gcdOfStrings("ABC", "ABCABC"), "ABC")
+	is.Equal(gcdOfStrings("ABC", "ABCDEF"), "")
+	is.Equal(gcdOfStrings("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA", "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"), "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA")
+}
+func gcdOfStrings(str1 string, str2 string) string {
+	if len(str1) == 0 {
+		return ""
+	}
+	runes1 := []rune(str1)
+	runes2 := []rune(str2)
+
+	n := max(len(runes1), len(runes2))
+	m := min(len(runes1), len(runes2))
+
+	if len(runes2) == m {
+		runes1, runes2 = runes2, runes1
+	}
+
+	if isRepeating(runes1, runes2) {
+		return string(runes1)
+	}
+
+	for i := n; i > 0; i-- {
+		if runes1[i%len(runes1)] != runes2[i%len(runes2)] {
+			return ""
+		}
+		gcd := runes2[:i]
+		if isRepeating(gcd, runes1) && isRepeating(gcd, runes2) {
+			return string(gcd)
+		}
+	}
+
+	return ""
+}
+func isRepeating(str1, str2 []rune) bool {
+	if len(str1) > len(str2) {
+		return false
+	}
+	if len(str2)%len(str1) != 0 {
+		return false
+	}
+	for i := range str2 {
+		if str1[i%len(str1)] != str2[i] {
+			return false
+		}
+	}
+	return true
+}
+
+func canPlaceFlowers(flowerbed []int, n int) bool {
+	var c int
+
+	for i := 0; i < len(flowerbed); i++ {
+		if (i == 0 || flowerbed[i-1] == 0) &&
+			flowerbed[i] == 0 &&
+			(i == len(flowerbed)-1 || flowerbed[i+1] == 0) {
+			c++
+			flowerbed[i] = 1
+		}
+	}
+
+	return c >= n
+}
+
+func TestFlowers(t *testing.T) {
+	is := is.New(t)
+	is.Equal(canPlaceFlowers([]int{1, 0, 0, 0, 1}, 1), true)
+	is.Equal(canPlaceFlowers([]int{0, 0, 1, 0, 1}, 1), true)
+	is.Equal(canPlaceFlowers([]int{1, 0, 1, 0, 0}, 1), true)
+}
+
+func dailyTemperatures(temperatures []int) []int {
+	answers := make([]int, len(temperatures))
+	var stack  [][2]int
+	push := func(v int) {
+		if len(stack) == 0 {
+			stack = append(stack, [2]int{v, 1})
+			return
+		}
+		end := len(stack)-1
+		if v < stack[end][0]{
+			stack = append(stack, [2]int{v, 1})
+			return
+
+		}
+		if v == stack[end][0] {
+			stack[len(stack)-1][1]++
+			return
+		}
+
+		var vs = [2]int{v, 1}
+		// for ; end>0; end-- {	
+		// 	if stack[end][0]<vs[0] {
+		// 		vs[1]+=stack[end][1]
+		// 		continue
+		// 	}
+		// 	break
+		// }
+		stack = append(stack, vs)
+	}
+
+	for i := len(temperatures) - 2; i >= 0; i-- {
+		push(temperatures[i+1])
+		currentTemp := temperatures[i]
+		days := 1
+		end := len(stack)-1
+		for j := range stack {
+			nextTemp := stack[end-j]
+			if currentTemp < nextTemp[0] {
+				answers[i] = days
+				break
+			}
+			days+=nextTemp[1]
+		}
+	}
+
+	return answers
+}
+
+func TestTemps(t *testing.T) {
+	is := is.New(t)
+	is.Equal(dailyTemperatures(
+		[]int{73, 74, 75, 71, 69, 72, 76, 73}),
+		[]int{1, 1, 4, 2, 1, 1, 0, 0})
+	is.Equal(dailyTemperatures(
+		[]int{99,99,99,99,100}), []int{4,3,2,1,0})	
+}

ranger/rangefunc.go

@@ -0,0 +1,12 @@
+package main
+
+
+func countRF(n int) func(yield func(int) bool) {
+	return func(yield func(int) bool) {
+		for i := range n {
+			if !yield(i) {
+				return
+			}
+		}
+	}
+} 

search.go

@@ -42,30 +42,6 @@ func (pq *priorityQueue[T]) ExtractMin() *T {
 	return elem
 }
 
-type stack[T any] []T
-
-func Stack[T any](a ...T) *stack[T] {
-	var s stack[T] = a
-	return &s
-}
-func (s *stack[T]) Push(a ...T) {
-	if s == nil {
-		return
-	}
-	*s = append(*s, a...)
-}
-func (s *stack[T]) IsEmpty() bool {
-	return s == nil || len(*s) == 0
-}
-func (s *stack[T]) Pop() T {
-	var a T
-	if s.IsEmpty() {
-		return a
-	}
-	a, *s = (*s)[len(*s)-1], (*s)[:len(*s)-1]
-	return a
-}
-
 // ManhattanDistance the distance between two points measured along axes at right angles.
 func ManhattanDistance[T integer](a, b Point[T]) T {
 	return ABS(a[0]-b[0]) + ABS(a[1]-b[1])

set_test.go

@@ -0,0 +1,27 @@
+package aoc_test
+
+import (
+	"sort"
+	"testing"
+
+	"github.com/matryer/is"
+	aoc "go.sour.is/advent-of-code"
+)
+
+func TestSet(t *testing.T) {
+	is := is.New(t)
+
+	s := aoc.Set(1, 2, 3)
+	is.True(!s.Has(0))
+	is.True(s.Has(1))
+	is.True(s.Has(2))
+	is.True(s.Has(3))
+	is.True(!s.Has(4))
+
+	s.Add(4)
+	is.True(s.Has(4))
+
+	items := s.Items()
+	sort.Ints(items)
+	is.Equal(items, []int{1, 2, 3, 4})
+}