HashHeap (#13)

* hash heap

README.md

@@ -27,7 +27,7 @@ data containers and algorithms to simplify business development.
   - [Filter](#filter)
 - [Heap](#heap)
   - [N-Way Heap](#n-way-heap)
-  - [N-Way Indexed Heap](#n-way-indexed-heap)
+  - [HashHeap](#hashheap)
 - [Stack](#stack)
 - [Queue](#queue)
 - [Deque](#deque)
@@ -128,9 +128,9 @@ func main() {
 
 ```
 
-#### N-Way Indexed Heap
+#### HashHeap
 
-Extends the normal heap with update and delete functions, often used in time heap algorithms.
+Heap structure with hash index.
 
 ```go
 package main
@@ -140,17 +140,20 @@ import (
 )
 
 func main() {
-    var h = heap.NewIndexedHeap[int, struct{}](heap.Quadratic, func(a, b int) bool { return a > b })
-    h.Push(1, struct{}{})
-    h.Push(3, struct{}{})
-    h.Push(5, struct{}{})
-    h.Push(2, struct{}{})
-    h.Push(4, struct{}{})
-    h.Push(6, struct{}{})
-    h.DeleteByIndex(5)
-    h.UpdateKeyByIndex(3, 7)
+    var h = heap.NewHashHeap[string, int](func(a, b int) bool { return a < b })
+    h.Set("a", 1)
+    h.Set("b", 2)
+    h.Set("c", 3)
+    h.Set("d", 4)
+    h.Set("e", 5)
+    h.Set("f", 6)
+
+    h.Delete("c")
+    h.Set("d", 0)
+    h.Set("g", 3)
     for h.Len() > 0 {
-        println(h.Pop().Key())
+        ele := h.Pop()
+        println(ele.Key(), ele.Value())
     }
 }
 

README_CN.md

@@ -19,12 +19,12 @@
 - [简介](#简介)
 - [目录](#目录)
 - [动态数组](#动态数组)
-    - [去重](#去重)
-    - [排序](#排序)
-    - [过滤](#过滤)
+  - [去重](#去重)
+  - [排序](#排序)
+  - [过滤](#过滤)
 - [堆](#堆)
-    - [N叉堆](#n叉堆)
-    - [N叉索引堆](#n叉索引堆)
+  - [N叉堆](#n叉堆)
+  - [哈希堆](#哈希堆)
 - [栈](#栈)
 - [队列](#队列)
 - [双端队列](#双端队列)
@@ -123,9 +123,9 @@ func main() {
 
 ```
 
-#### N叉索引堆
+#### 哈希堆
 
-在普通堆的基础上拓展了更新和删除功能, 常用于时间堆算法.
+带哈希索引的堆结构.
 
 ```go
 package main
@@ -135,17 +135,20 @@ import (
 )
 
 func main() {
-    var h = heap.NewIndexedHeap[int, struct{}](heap.Quadratic, func(a, b int) bool { return a > b })
-    h.Push(1, struct{}{})
-    h.Push(3, struct{}{})
-    h.Push(5, struct{}{})
-    h.Push(2, struct{}{})
-    h.Push(4, struct{}{})
-    h.Push(6, struct{}{})
-    h.DeleteByIndex(5)
-    h.UpdateKeyByIndex(3, 7)
+    var h = heap.NewHashHeap[string, int](func(a, b int) bool { return a < b })
+    h.Set("a", 1)
+    h.Set("b", 2)
+    h.Set("c", 3)
+    h.Set("d", 4)
+    h.Set("e", 5)
+    h.Set("f", 6)
+
+    h.Delete("c")
+    h.Set("d", 0)
+    h.Set("g", 3)
     for h.Len() > 0 {
-        println(h.Pop().Key())
+        ele := h.Pop()
+        println(ele.Key(), ele.Value())
     }
 }
 

algo/algorithm.go

@@ -4,6 +4,7 @@ import (
 	"github.com/lxzan/dao/types/cmp"
 	"reflect"
 	"strconv"
+	"strings"
 )
 
 // ToString 数字转字符串
@@ -135,13 +136,14 @@ func Map[A any, B any](arr []A, transfer func(i int, v A) B) []B {
 
 // Filter 过滤器
 func Filter[T any, A ~[]T](arr A, check func(i int, v T) bool) A {
-	var results = make([]T, 0, len(arr))
+	var j = 0
 	for i, v := range arr {
 		if check(i, v) {
-			results = append(results, arr[i])
+			arr[j] = arr[i]
+			j++
 		}
 	}
-	return results
+	return arr[:j]
 }
 
 // IsZero 零值判断
@@ -171,11 +173,26 @@ func NotNil(v any) bool {
 }
 
 // GroupBy 分组
-func GroupBy[T any, A ~[]T, K cmp.Ordered](arr A, transfer func(i int, v T) K) map[K]A {
+func GroupBy[T any, K cmp.Ordered, A ~[]T](arr A, transfer func(i int, v T) K) map[K]A {
 	var m = make(map[K]A, len(arr))
 	for index, value := range arr {
 		key := transfer(index, value)
 		m[key] = append(m[key], value)
 	}
 	return m
 }
+
+func SplitWithCallback(s string, sep string, cb func(index int, item string) bool) {
+	var n = len(sep)
+	var index = 0
+	for i := strings.Index(s, sep); i != -1; i = strings.Index(s, sep) {
+		if !cb(index, s[:i]) {
+			return
+		}
+		index++
+		if i+n <= len(s) {
+			s = s[i+n:]
+		}
+	}
+	cb(index, s)
+}

algo/algorithm_test.go

@@ -171,11 +171,23 @@ func TestContains(t *testing.T) {
 }
 
 func TestFilter(t *testing.T) {
-	var arr = []int{1, 2, 3, 4}
-	arr = Filter(arr, func(i int, item int) bool {
-		return item%2 == 0
+	t.Run("", func(t *testing.T) {
+		var arr = []int{1, 2, 3, 4}
+		arr = Filter(arr, func(i int, item int) bool { return item%2 == 0 })
+		assert.ElementsMatch(t, arr, []int{2, 4})
+	})
+
+	t.Run("", func(t *testing.T) {
+		var arr = []int{1, 2, 3, 4}
+		arr = Filter(arr, func(i int, item int) bool { return item%2 == 1 })
+		assert.ElementsMatch(t, arr, []int{1, 3})
+	})
+
+	t.Run("", func(t *testing.T) {
+		var arr = []int{}
+		arr = Filter(arr, func(i int, item int) bool { return item%2 == 0 })
+		assert.ElementsMatch(t, arr, []int{})
 	})
-	assert.ElementsMatch(t, arr, []int{2, 4})
 }
 
 func TestIsZero(t *testing.T) {
@@ -240,6 +252,10 @@ func TestIsNil(t *testing.T) {
 	assert.True(t, IsNil(conn1))
 	assert.True(t, IsNil(conn2))
 	assert.False(t, IsNil(conn3))
+
+	assert.False(t, NotNil(conn1))
+	assert.False(t, NotNil(conn2))
+	assert.True(t, NotNil(conn3))
 }
 
 func TestNotNil(t *testing.T) {
@@ -253,3 +269,35 @@ func TestWithDefault(t *testing.T) {
 	assert.Equal(t, WithDefault("", "1"), "1")
 	assert.Equal(t, WithDefault("2", "1"), "2")
 }
+
+func TestSplitWithCallback(t *testing.T) {
+	t.Run("", func(t *testing.T) {
+		var path = "/api/v1/greet"
+		var values []string
+		SplitWithCallback(path, "/", func(index int, item string) bool {
+			values = append(values, item)
+			return true
+		})
+		assert.ElementsMatch(t, values, []string{"", "api", "v1", "greet"})
+	})
+
+	t.Run("", func(t *testing.T) {
+		var path = "/api/v1/greet/"
+		var values []string
+		SplitWithCallback(path, "/", func(index int, item string) bool {
+			values = append(values, item)
+			return true
+		})
+		assert.ElementsMatch(t, values, []string{"", "api", "v1", "greet", ""})
+	})
+
+	t.Run("", func(t *testing.T) {
+		var path = "/api/v1/greet"
+		var values []string
+		SplitWithCallback(path, "/", func(index int, item string) bool {
+			values = append(values, item)
+			return len(values) < 2
+		})
+		assert.ElementsMatch(t, values, []string{"", "api"})
+	})
+}