2017.4.16

Author: Juntaran

Data_Structure/Heap/heap.go

@@ -0,0 +1,124 @@
+package heap
+
+import (
+	"sync"
+)
+
+type Item interface {
+	Less(than Item) bool
+}
+
+type Heap struct {
+	data 	[]Item
+	min 	bool
+	mutex 	sync.Mutex
+}
+
+// 新建一个堆
+func New() *Heap {
+	newHeap := &Heap{
+		data: 	make([]Item, 0),
+	}
+	return newHeap
+}
+
+// 新建一个小顶堆
+func NewMin() *Heap {
+	newHeap := &Heap{
+		data: 	make([]Item, 0),
+		min:	true,
+	}
+	return newHeap
+}
+
+// 新建一个大顶堆
+func NewMax() *Heap {
+	newHeap := &Heap{
+		data: 	make([]Item, 0),
+		min:	false,
+	}
+	return newHeap
+}
+
+// 堆是否为空
+func (h *Heap) IsEmpty() bool {
+	return len(h.data) == 0
+}
+
+// 堆大小
+func (h *Heap) Size() int {
+	return len(h.data)
+}
+
+// 获取元素
+func (h *Heap) Get(index int) Item {
+	return h.data[index]
+}
+
+// 插入元素
+func (h *Heap) Insert(n Item) {
+	h.mutex.Lock()
+	defer h.mutex.Unlock()
+	{
+		h.data = append(h.data, n)
+		h.siftUp()
+		return
+	}
+}
+
+// 取出元素
+func (h *Heap) Extract() (element Item) {
+	h.mutex.Lock()
+	defer h.mutex.Unlock()
+	{
+		if h.Size() == 0 {
+			return
+		}
+		element = h.data[0]
+		last := h.data[h.Size()-1]
+		if h.Size() == 1 {
+			h.data = nil
+			return
+		}
+		h.data = append([]Item{last}, h.data[1:h.Size()-1]...)
+		h.siftDown()
+		return
+	}
+}
+
+// 上移操作
+func (h *Heap) siftUp() {
+	for i, parent := h.Size()-1, h.Size()-1; i > 0; i = parent {
+		parent = i >> 1
+		// 如果i位置小于 其父节点，交换
+		if h.Less(h.Get(i), h.Get(parent)) {
+			h.data[parent], h.data[i] = h.data[i], h.data[parent]
+		} else {
+			break
+		}
+	}
+}
+
+// 下移操作
+func (h *Heap) siftDown() {
+	for i, child := 0, 1; i < h.Size() && i<<1+1 < h.Size(); i = child {
+		child = i << 1 + 1
+		// 两个孩子节点之间交换
+		if child+1 <= h.Size()-1 && h.Less(h.Get(child+1), h.Get(child)) {
+			child ++
+		}
+		// 父节点如果小于子节点，交换
+		if h.Less(h.Get(i), h.Get(child)) {
+			break
+		}
+	}
+}
+
+
+func (h *Heap) Less(a, b Item) bool {
+	if h.min {
+		return a.Less(b)
+	} else {
+		return b.Less(a)
+	}
+}

Data_Structure/Heap/main/main.go

@@ -0,0 +1,64 @@
+/**
+  * Author: Juntaran
+  * Email:  Jacinthmail@gmail.com
+  * Date:   2017/4/15 10:51
+  */
+
+package main
+
+import (
+	"Golang_Algorithm/Data_Structure/Heap"
+	"fmt"
+	"log"
+)
+
+func main() {
+	// 最小堆测试
+	h1 := heap.NewMin()
+	h1.Insert(heap.Int(8))
+	h1.Insert(heap.Int(7))
+	h1.Insert(heap.Int(6))
+	h1.Insert(heap.Int(3))
+	h1.Insert(heap.Int(1))
+	h1.Insert(heap.Int(0))
+	h1.Insert(heap.Int(2))
+	h1.Insert(heap.Int(4))
+	h1.Insert(heap.Int(9))
+	h1.Insert(heap.Int(5))
+
+	sorted := make([]heap.Int, 0)
+	for h1.Size() > 0 {
+		sorted = append(sorted, h1.Extract().(heap.Int))
+	}
+	for i := 0; i < len(sorted)-2; i++ {
+		if sorted[i] > sorted[i+1] {
+			fmt.Println(sorted)
+		} else {
+			log.Println("Error")
+		}
+	}
+
+	h2 := heap.NewMin()
+	h2.Insert(heap.Int(8))
+	h2.Insert(heap.Int(7))
+	h2.Insert(heap.Int(6))
+	h2.Insert(heap.Int(3))
+	h2.Insert(heap.Int(1))
+	h2.Insert(heap.Int(0))
+	h2.Insert(heap.Int(2))
+	h2.Insert(heap.Int(4))
+	h2.Insert(heap.Int(9))
+	h2.Insert(heap.Int(5))
+
+	sorted = make([]heap.Int, 0)
+	for h2.Size() > 0 {
+		sorted = append(sorted, h2.Extract().(heap.Int))
+	}
+	for i := 0; i < len(sorted)-2; i++ {
+		if sorted[i] > sorted[i+1] {
+			fmt.Println(sorted)
+		} else {
+			log.Println("Error")
+		}
+	}
+}

Data_Structure/Heap/util.go

@@ -0,0 +1,7 @@
+package heap
+
+type Int int
+
+func (x Int) Less(than Item) bool {
+	return x < than.(Int)
+}