成功 旋转3

vbtkey/iterator.go

@@ -24,6 +24,18 @@ func NewIterator(n *Node) *Iterator {
 	return iter
 }
 
+func NewIteratorWithCap(n *Node, cap int) *Iterator {
+	iter := &Iterator{tstack: lastack.NewWithCap(cap)}
+	iter.up = n
+	return iter
+}
+
+func (iter *Iterator) SetNode(n *Node) {
+	iter.up = n
+	iter.dir = 0
+	iter.tstack.Clear()
+}
+
 func (iter *Iterator) Value() interface{} {
 	return iter.cur.value
 }
@@ -46,9 +58,10 @@ func (iter *Iterator) Right() bool {
 	return false
 }
 
-func GetNext(cur *Node, idx int) *Node {
+func (iter *Iterator) GetNext(cur *Node, idx int) *Node {
 
-	iter := NewIterator(cur)
+	// iter := NewIterator(cur)
+	iter.SetNode(cur)
 	iter.curPushNextStack(iter.up)
 	iter.up = iter.getNextUp(iter.up)
 
@@ -103,9 +116,10 @@ func (iter *Iterator) Next() (result bool) {
 
 	return false
 }
-func GetPrev(cur *Node, idx int) *Node {
+func (iter *Iterator) GetPrev(cur *Node, idx int) *Node {
 
-	iter := NewIterator(cur)
+	// iter := NewIterator(cur)
+	iter.SetNode(cur)
 	iter.curPushPrevStack(iter.up)
 	iter.up = iter.getPrevUp(iter.up)
 

vbtkey/vbtkey.go

@@ -28,10 +28,12 @@ func (n *Node) String() string {
 type Tree struct {
 	root    *Node
 	Compare compare.Compare
+
+	iter *Iterator
 }
 
 func New(Compare compare.Compare) *Tree {
-	return &Tree{Compare: Compare}
+	return &Tree{Compare: Compare, iter: NewIteratorWithCap(nil, 16)}
 }
 
 func (tree *Tree) String() string {
@@ -264,7 +266,8 @@ func (tree *Tree) GetRange(k1, k2 interface{}) (result []interface{}) {
 
 		result = make([]interface{}, 0, 16)
 
-		iter := NewIterator(min)
+		tree.iter.SetNode(min)
+		iter := tree.iter
 		for iter.Next() {
 			result = append(result, iter.Value())
 			if iter.cur == max {
@@ -289,7 +292,8 @@ func (tree *Tree) GetRange(k1, k2 interface{}) (result []interface{}) {
 
 		result = make([]interface{}, 0, 16)
 
-		iter := NewIterator(max)
+		tree.iter.SetNode(max)
+		iter := tree.iter
 		for iter.Prev() {
 			result = append(result, iter.Value())
 			if iter.cur == min {
@@ -339,7 +343,8 @@ func (tree *Tree) getArountNode(key interface{}) (result [3]*Node) {
 			n = n.children[1]
 			lastc = c
 		case 0:
-			iter := NewIterator(n)
+			tree.iter.SetNode(n)
+			iter := tree.iter
 			iter.Prev()
 			for iter.Prev() {
 				if tree.Compare(iter.cur.value, n.value) == 0 {
@@ -360,21 +365,21 @@ func (tree *Tree) getArountNode(key interface{}) (result [3]*Node) {
 
 		if result[1] != nil {
 
-			result[0] = GetPrev(result[1], 1)
-			result[2] = GetNext(result[1], 1)
+			result[0] = tree.iter.GetPrev(result[1], 1)
+			result[2] = tree.iter.GetNext(result[1], 1)
 		} else {
 			result[0] = last
-			result[2] = GetNext(last, 1)
+			result[2] = tree.iter.GetNext(last, 1)
 		}
 
 	case -1:
 
 		if result[1] != nil {
-			result[0] = GetPrev(result[1], 1)
-			result[2] = GetNext(result[1], 1)
+			result[0] = tree.iter.GetPrev(result[1], 1)
+			result[2] = tree.iter.GetNext(result[1], 1)
 		} else {
 			result[2] = last
-			result[0] = GetPrev(last, 1)
+			result[0] = tree.iter.GetPrev(last, 1)
 		}
 
 	case 0:
@@ -382,8 +387,8 @@ func (tree *Tree) getArountNode(key interface{}) (result [3]*Node) {
 		if result[1] == nil {
 			return
 		}
-		result[0] = GetPrev(result[1], 1)
-		result[2] = GetNext(result[1], 1)
+		result[0] = tree.iter.GetPrev(result[1], 1)
+		result[2] = tree.iter.GetNext(result[1], 1)
 	}
 	return
 }
@@ -397,7 +402,9 @@ func (tree *Tree) GetNode(value interface{}) (*Node, bool) {
 		case 1:
 			n = n.children[1]
 		case 0:
-			iter := NewIterator(n)
+
+			tree.iter.SetNode(n)
+			iter := tree.iter
 			iter.Prev()
 			for iter.Prev() {
 				if tree.Compare(iter.cur.value, n.value) == 0 {
@@ -746,7 +753,6 @@ func (tree *Tree) rrotate3(cur *Node) {
 	mov.key, mov.value, cur.key, cur.value = cur.key, cur.value, mov.key, mov.value //交换值达到, 相对位移
 
 	cur.children[r] = mov
-	mov.size = 1
 
 	cur.children[l] = mov.children[l]
 	cur.children[l].parent = cur
@@ -800,7 +806,6 @@ func (tree *Tree) lrotate3(cur *Node) {
 	mov.key, mov.value, cur.key, cur.value = cur.key, cur.value, mov.key, mov.value //交换值达到, 相对位移
 
 	cur.children[r] = mov
-	mov.size = 1
 
 	cur.children[l] = mov.children[l]
 	cur.children[l].parent = cur