diff --git a/avl/avl.go b/avl/avl.go
index d9cdcb0..1f4a8f1 100644
--- a/avl/avl.go
+++ b/avl/avl.go
@@ -120,6 +120,19 @@ func (avl *Tree) Remove(key interface{}) *Node {
return nil
}
+// Values 返回先序遍历的值
+func (avl *Tree) Values() []interface{} {
+ mszie := 0
+ if avl.root != nil {
+ mszie = avl.size
+ }
+ result := make([]interface{}, 0, mszie)
+ avl.Traversal(func(v interface{}) {
+ result = append(result, v)
+ }, DLR)
+ return result
+}
+
func (avl *Tree) Get(key interface{}) (interface{}, bool) {
n, ok := avl.GetNode(key)
if ok {
@@ -143,57 +156,35 @@ func (avl *Tree) GetAround(key interface{}) (result [3]interface{}) {
}
func (avl *Tree) GetAroundNode(value interface{}) (result [3]*Node) {
- n := avl.root
+ if cur, ok := avl.GetNode(value); ok {
- for {
+ var iter *Iterator
- if n == nil {
- return
+ iter = NewIterator(cur)
+ iter.curPushPrevStack(iter.up)
+ iter.up = iter.getPrevUp(iter.up)
+
+ if v, ok := iter.tstack.Pop(); ok {
+ result[0] = v.(*Node)
+ // iter.curPushPrevStack(iter.cur)
+ } else {
+ result[0] = iter.up
}
- lastc := 0
- switch c := avl.comparator(value, n.value); c {
- case -1:
- if c != -lastc {
- result[0] = n
- }
- lastc = c
- n = n.children[0]
- case 1:
- if c != -lastc {
- result[2] = n
- }
- lastc = c
- n = n.children[1]
- case 0:
+ iter = NewIterator(cur)
+ iter.curPushNextStack(iter.up)
+ iter.up = iter.getNextUp(iter.up)
- switch lastc {
- case -1:
- if n.children[1] != nil {
- result[0] = n.children[1]
- }
- case 1:
- if n.children[0] != nil {
- result[2] = n.children[0]
- }
- case 0:
-
- if n.children[1] != nil {
- result[0] = n.children[1]
- }
- if n.children[0] != nil {
- result[2] = n.children[0]
- }
-
- result[1] = n
- return
- }
-
- default:
- panic("Get comparator only is allowed in -1, 0, 1")
+ if v, ok := iter.tstack.Pop(); ok {
+ result[2] = v.(*Node)
+ // iter.curPushNextStack(iter.cur)
+ } else {
+ result[2] = iter.up
}
+ result[1] = cur
}
+ return
}
func (avl *Tree) GetNode(value interface{}) (*Node, bool) {
@@ -251,47 +242,64 @@ func (avl *Tree) debugString() string {
return str
}
-func (avl *Tree) TraversalBreadth() (result []interface{}) {
- result = make([]interface{}, 0, avl.size)
- var traverasl func(cur *Node)
- traverasl = func(cur *Node) {
- if cur == nil {
- return
- }
- result = append(result, cur.value)
- traverasl(cur.children[0])
- traverasl(cur.children[1])
- }
- traverasl(avl.root)
- return
-}
+type TraversalMethod int
-func (avl *Tree) TraversalDepth(leftright int) (result []interface{}) {
- result = make([]interface{}, 0, avl.size)
- if leftright < 0 {
+const (
+ _ TraversalMethod = iota
+ //DLR 前序遍历
+ DLR
+ //LDR 中序遍历
+ LDR
+ //LRD 后序遍历
+ LRD
+)
+
+// Traversal 遍历的方法
+func (avl *Tree) Traversal(every func(v interface{}), traversalMethod ...interface{}) {
+ if avl.root == nil {
+ return
+ }
+
+ method := LDR
+ if len(traversalMethod) != 0 {
+ method = traversalMethod[0].(TraversalMethod)
+ }
+
+ switch method {
+ case DLR:
var traverasl func(cur *Node)
traverasl = func(cur *Node) {
if cur == nil {
return
}
traverasl(cur.children[0])
- result = append(result, cur.value)
+ every(cur.value)
traverasl(cur.children[1])
}
traverasl(avl.root)
- } else {
+ case LRD:
var traverasl func(cur *Node)
traverasl = func(cur *Node) {
if cur == nil {
return
}
traverasl(cur.children[1])
- result = append(result, cur.value)
+ every(cur.value)
traverasl(cur.children[0])
}
traverasl(avl.root)
+ case LDR:
+ var traverasl func(cur *Node)
+ traverasl = func(cur *Node) {
+ if cur == nil {
+ return
+ }
+ every(cur.value)
+ traverasl(cur.children[0])
+ traverasl(cur.children[1])
+ }
+ traverasl(avl.root)
}
-
return
}
@@ -564,7 +572,6 @@ func abs(n int) int {
}
func (avl *Tree) fixRemoveHeight(cur *Node) {
-
for {
lefth, rigthh, lrmax := getMaxAndChildrenHeight(cur)
diff --git a/avl/avl_test.go b/avl/avl_test.go
index f88523a..baf3551 100644
--- a/avl/avl_test.go
+++ b/avl/avl_test.go
@@ -16,7 +16,7 @@ import (
"github.com/emirpasic/gods/utils"
)
-const CompartorSize = 1000000
+const CompartorSize = 100
const NumberMax = 600
func TestSave(t *testing.T) {
@@ -124,7 +124,7 @@ func TestGetAround(t *testing.T) {
}
if spew.Sprint(avl.GetAround(40)) != "[40 40 30]" {
- t.Error("avl.GetAround(40)) is error", spew.Sprint(avl.GetAround(50)))
+ t.Error("avl.GetAround(40)) is error", spew.Sprint(avl.GetAround(40)))
}
if spew.Sprint(avl.GetAround(50)) != "[<nil> 50 40]" {
@@ -241,7 +241,7 @@ ALL:
for i := 0; i < 100; i++ {
avl.Remove(l[i])
gods.Remove(l[i])
- s1 := spew.Sprint(avl.TraversalDepth(-1))
+ s1 := spew.Sprint(avl.Values())
s2 := spew.Sprint(gods.Values())
if s1 != s2 {
t.Error("avl remove error", "avlsize = ", avl.Size())
@@ -251,6 +251,7 @@ ALL:
}
}
}
+
}
func TestRemove(t *testing.T) {
@@ -279,7 +280,7 @@ ALL:
for i := 0; i < 10; i++ {
avl.Remove(l[i])
gods.Remove(l[i])
- if spew.Sprint(gods.Values()) != spew.Sprint(avl.TraversalDepth(-1)) && avl.size != 0 {
+ if spew.Sprint(gods.Values()) != spew.Sprint(avl.Values()) && avl.size != 0 {
// if gods.String() != avl.String() && gods.Size() != 0 && avl.size != 0 {
t.Error(src1)
t.Error(src2)
@@ -316,27 +317,6 @@ func BenchmarkIterator(b *testing.B) {
}
-func BenchmarkGodsIterator(b *testing.B) {
- tree := avltree.NewWithIntComparator()
-
- l := loadTestData()
- b.N = len(l)
-
- for _, v := range l {
- tree.Put(v, v)
- }
-
- b.ResetTimer()
- b.StartTimer()
- iter := tree.Iterator()
- for iter.Next() {
- }
- for iter.Prev() {
- }
- for iter.Next() {
- }
-}
-
func BenchmarkRemove(b *testing.B) {
tree := New(utils.IntComparator)
diff --git a/avl/iterator.go b/avl/iterator.go
index 1236404..b0309ee 100644
--- a/avl/iterator.go
+++ b/avl/iterator.go
@@ -20,8 +20,10 @@ func initIterator(avltree *Tree) *Iterator {
return iter
}
-func NewIterator(tree *Tree) *Iterator {
- return initIterator(tree)
+func NewIterator(n *Node) *Iterator {
+ iter := &Iterator{tstack: lastack.New()}
+ iter.up = n
+ return iter
}
func (iter *Iterator) Value() interface{} {
diff --git a/avlindex/avlindex.go b/avlindex/avlindex.go
index 339af96..45b99a2 100644
--- a/avlindex/avlindex.go
+++ b/avlindex/avlindex.go
@@ -36,8 +36,10 @@ func New(comparator utils.Comparator) *Tree {
func (avl *Tree) String() string {
str := "AVLTree\n"
+ if avl.root == nil {
+ return str + "nil"
+ }
output(avl.root, "", true, &str)
-
return str
}
@@ -55,7 +57,7 @@ func (avl *Tree) Size() int {
func (avl *Tree) Remove(key interface{}) *Node {
if n, ok := avl.GetNode(key); ok {
- if avl.root == n {
+ if avl.root.size == 1 {
avl.root = nil
return n
}
@@ -112,6 +114,19 @@ func (avl *Tree) Remove(key interface{}) *Node {
return nil
}
+// Values 返回先序遍历的值
+func (avl *Tree) Values() []interface{} {
+ mszie := 0
+ if avl.root != nil {
+ mszie = avl.root.size
+ }
+ result := make([]interface{}, 0, mszie)
+ avl.Traversal(func(v interface{}) {
+ result = append(result, v)
+ }, LDR)
+ return result
+}
+
func (avl *Tree) Get(key interface{}) (interface{}, bool) {
n, ok := avl.GetNode(key)
if ok {
@@ -121,6 +136,35 @@ func (avl *Tree) Get(key interface{}) (interface{}, bool) {
}
func (avl *Tree) GetRange(min, max interface{}) []interface{} {
+
+ var minN *Node
+ for minN = avl.root; minN != nil; {
+ switch c := avl.comparator(min, minN.value); c {
+ case -1:
+ minN = minN.children[0]
+ case 1:
+ minN = minN.children[1]
+ case 0:
+ break
+ default:
+ panic("Get comparator only is allowed in -1, 0, 1")
+ }
+ }
+
+ var maxN *Node
+ for maxN = avl.root; maxN != nil; {
+ switch c := avl.comparator(min, maxN.value); c {
+ case -1:
+ maxN = maxN.children[0]
+ case 1:
+ maxN = maxN.children[1]
+ case 0:
+ break
+ default:
+ panic("Get comparator only is allowed in -1, 0, 1")
+ }
+ }
+
return nil
}
@@ -135,57 +179,36 @@ func (avl *Tree) GetAround(key interface{}) (result [3]interface{}) {
}
func (avl *Tree) GetAroundNode(value interface{}) (result [3]*Node) {
- n := avl.root
- for {
+ if cur, ok := avl.GetNode(value); ok {
- if n == nil {
- return
+ var iter *Iterator
+
+ iter = NewIterator(cur)
+ iter.curPushPrevStack(iter.up)
+ iter.up = iter.getPrevUp(iter.up)
+
+ if v, ok := iter.tstack.Pop(); ok {
+ result[0] = v.(*Node)
+ // iter.curPushPrevStack(iter.cur)
+ } else {
+ result[0] = iter.up
}
- lastc := 0
- switch c := avl.comparator(value, n.value); c {
- case -1:
- if c != -lastc {
- result[0] = n
- }
- lastc = c
- n = n.children[0]
- case 1:
- if c != -lastc {
- result[2] = n
- }
- lastc = c
- n = n.children[1]
- case 0:
+ iter = NewIterator(cur)
+ iter.curPushNextStack(iter.up)
+ iter.up = iter.getNextUp(iter.up)
- switch lastc {
- case -1:
- if n.children[1] != nil {
- result[0] = n.children[1]
- }
- case 1:
- if n.children[0] != nil {
- result[2] = n.children[0]
- }
- case 0:
-
- if n.children[1] != nil {
- result[0] = n.children[1]
- }
- if n.children[0] != nil {
- result[2] = n.children[0]
- }
-
- result[1] = n
- return
- }
-
- default:
- panic("Get comparator only is allowed in -1, 0, 1")
+ if v, ok := iter.tstack.Pop(); ok {
+ result[2] = v.(*Node)
+ // iter.curPushNextStack(iter.cur)
+ } else {
+ result[2] = iter.up
}
+ result[1] = cur
}
+ return
}
func (avl *Tree) GetNode(value interface{}) (*Node, bool) {
@@ -246,61 +269,107 @@ func (avl *Tree) Put(value interface{}) {
}
}
-func (avl *Tree) debugString() string {
- str := "AVLTree\n"
- outputfordebug(avl.root, "", true, &str)
- return str
-}
+type TraversalMethod int
-func (avl *Tree) TraversalBreadth() (result []interface{}) {
+const (
+ // L = left R = right D = Value(dest)
+ _ TraversalMethod = iota
+ //DLR 先值 然后左递归 右递归 下面同理
+ DLR
+ //LDR 先从左边有序访问到右边 从小到大
+ LDR
+ // LRD 同理
+ LRD
+
+ // DRL 同理
+ DRL
+
+ // RDL 先从右边有序访问到左边 从大到小
+ RDL
+
+ // RLD 同理
+ RLD
+)
+
+// Traversal 遍历的方法
+func (avl *Tree) Traversal(every func(v interface{}), traversalMethod ...interface{}) {
if avl.root == nil {
return
}
- result = make([]interface{}, 0, avl.root.size)
- var traverasl func(cur *Node)
- traverasl = func(cur *Node) {
- if cur == nil {
- return
+ method := DLR
+ if len(traversalMethod) != 0 {
+ method = traversalMethod[0].(TraversalMethod)
+ }
+
+ switch method {
+ case DLR:
+ var traverasl func(cur *Node)
+ traverasl = func(cur *Node) {
+ if cur == nil {
+ return
+ }
+ every(cur.value)
+ traverasl(cur.children[0])
+ traverasl(cur.children[1])
}
- result = append(result, cur.value)
- traverasl(cur.children[0])
- traverasl(cur.children[1])
- }
- traverasl(avl.root)
- return
-}
-
-func (avl *Tree) TraversalDepth(leftright int) (result []interface{}) {
- if avl.root == nil {
- return
- }
-
- result = make([]interface{}, 0, avl.root.size)
- if leftright < 0 {
+ traverasl(avl.root)
+ case LDR:
var traverasl func(cur *Node)
traverasl = func(cur *Node) {
if cur == nil {
return
}
traverasl(cur.children[0])
- result = append(result, cur.value)
+ every(cur.value)
traverasl(cur.children[1])
}
traverasl(avl.root)
- } else {
+ case LRD:
+ var traverasl func(cur *Node)
+ traverasl = func(cur *Node) {
+ if cur == nil {
+ return
+ }
+ traverasl(cur.children[0])
+ traverasl(cur.children[1])
+ every(cur.value)
+ }
+ traverasl(avl.root)
+ case DRL:
+ var traverasl func(cur *Node)
+ traverasl = func(cur *Node) {
+ if cur == nil {
+ return
+ }
+ every(cur.value)
+ traverasl(cur.children[0])
+ traverasl(cur.children[1])
+ }
+ traverasl(avl.root)
+ case RDL:
var traverasl func(cur *Node)
traverasl = func(cur *Node) {
if cur == nil {
return
}
traverasl(cur.children[1])
- result = append(result, cur.value)
+ every(cur.value)
traverasl(cur.children[0])
}
traverasl(avl.root)
+ case RLD:
+ var traverasl func(cur *Node)
+ traverasl = func(cur *Node) {
+ if cur == nil {
+ return
+ }
+ traverasl(cur.children[1])
+ traverasl(cur.children[0])
+ every(cur.value)
+ }
+ traverasl(avl.root)
}
-
return
}
@@ -503,11 +572,6 @@ func (avl *Tree) fixRemoveHeight(cur *Node) {
}
}
-// func abs(n int) int {
-// y := n >> 31
-// return (n ^ y) - y
-// }
-
func (avl *Tree) fixPutHeight(cur *Node, lefts, rigths int) {
if lefts > rigths {
l := cur.children[0]
@@ -598,3 +662,12 @@ func outputfordebug(node *Node, prefix string, isTail bool, str *string) {
outputfordebug(node.children[0], newPrefix, true, str)
}
}
+
+func (avl *Tree) debugString() string {
+ str := "AVLTree\n"
+ if avl.root == nil {
+ return str + "nil"
+ }
+ outputfordebug(avl.root, "", true, &str)
+ return str
+}
diff --git a/avlindex/avlindex_test.go b/avlindex/avlindex_test.go
index 6ddce3c..ec8b6a6 100644
--- a/avlindex/avlindex_test.go
+++ b/avlindex/avlindex_test.go
@@ -62,109 +62,70 @@ func loadTestData() []int {
return l
}
-// func TestIterator(t *testing.T) {
-// avl := New(utils.IntComparator)
-// for _, v := range []int{1, 2, 7, 4, 5, 6, 7, 14, 15, 20, 30, 21, 3} {
-// // t.Error(v)
-// avl.Put(v)
+func TestIterator(t *testing.T) {
+ avl := New(utils.IntComparator)
+ for _, v := range []int{7, 14, 14, 14, 16, 17, 20, 30, 21, 40, 40, 50, 3, 40, 40, 40, 15} {
+ avl.Put(v)
+ }
+ t.Error(avl.Values())
+ t.Error(avl.debugString())
+}
-// }
-// // ` AVLTree
-// // │ ┌── 30
-// // │ │ └── 21
-// // │ ┌── 20
-// // │ │ └── 15
-// // └── 14
-// // │ ┌── 7
-// // │ ┌── 7
-// // │ │ └── 6
-// // └── 5
-// // │ ┌── 4
-// // │ │ └── 3
-// // └── 2
-// // └── 1`
+func TestGetAround(t *testing.T) {
+ avl := New(utils.IntComparator)
+ for _, v := range []int{7, 14, 14, 14, 16, 17, 20, 30, 21, 40, 50, 3, 40, 40, 40, 15} {
+ avl.Put(v)
+ }
-// iter := avl.Iterator() // root start point
+ var Result string
-// l := []int{14, 15, 20, 21, 30}
+ Result = spew.Sprint(avl.GetAround(3))
+ if Result != "[7 3 <nil>]" {
+ t.Error("avl.GetAround(3)) is error", Result)
+ }
-// for i := 0; iter.Prev(); i++ {
-// if iter.Value().(int) != l[i] {
-// t.Error("iter prev error", iter.Value(), l[i])
-// }
-// }
+ Result = spew.Sprint(avl.GetAround(40))
+ if Result != "[40 40 30]" {
+ t.Error("avl.GetAround(40)) is error", Result)
+ }
-// iter.Prev()
-// if iter.Value().(int) != 30 {
-// t.Error("prev == false", iter.Value(), iter.Prev(), iter.Value())
-// }
-
-// l = []int{21, 20, 15, 14, 7, 7, 6, 5, 4, 3, 2, 1}
-// for i := 0; iter.Next(); i++ { // cur is 30 next is 21
-// if iter.Value().(int) != l[i] {
-// t.Error(iter.Value())
-// }
-// }
-
-// if iter.Next() != false {
-// t.Error("Next is error, cur is tail, val = 1 Next return false")
-// }
-// if iter.Value().(int) != 1 { // cur is 1
-// t.Error("next == false", iter.Value(), iter.Next(), iter.Value())
-// }
-
-// if iter.Prev() != true && iter.Value().(int) != 2 {
-// t.Error("next to prev is error")
-// }
-// }
-
-// func TestGetAround(t *testing.T) {
-// avl := New(utils.IntComparator)
-// for _, v := range []int{7, 14, 15, 20, 30, 21, 40, 40, 50, 3, 40, 40, 40} {
-// avl.Put(v)
-// }
-
-// if spew.Sprint(avl.GetAround(30)) != "[40 30 21]" {
-// t.Error("avl.GetAround(40)) is error", spew.Sprint(avl.GetAround(30)))
-// }
-
-// if spew.Sprint(avl.GetAround(40)) != "[40 40 30]" {
-// t.Error("avl.GetAround(40)) is error", spew.Sprint(avl.GetAround(50)))
-// }
-
-// if spew.Sprint(avl.GetAround(50)) != "[<nil> 50 40]" {
-// t.Error("avl.GetAround(40)) is error", spew.Sprint(avl.GetAround(50)))
-// }
-// }
+ Result = spew.Sprint(avl.GetAround(50))
+ if Result != "[<nil> 50 40]" {
+ t.Error("avl.GetAround(50)) is error", Result)
+ }
+}
// // for test error case
-// func TestPutComparatorRandom(t *testing.T) {
+func TestPutComparatorRandom(t *testing.T) {
-// for n := 0; n < 300000; n++ {
-// avl := New(utils.IntComparator)
-// godsavl := avltree.NewWithIntComparator()
+ for n := 0; n < 300000; n++ {
+ avl := New(utils.IntComparator)
+ godsavl := avltree.NewWithIntComparator()
-// content := ""
-// m := make(map[int]int)
-// for i := 0; len(m) < 10; i++ {
-// v := randomdata.Number(0, 65535)
-// if _, ok := m[v]; !ok {
-// m[v] = v
-// content += spew.Sprint(v) + ","
-// avl.Put(v)
-// godsavl.Put(v, v)
-// }
-// }
+ content := ""
+ m := make(map[int]int)
+ for i := 0; len(m) < 10; i++ {
+ v := randomdata.Number(0, 65535)
+ if _, ok := m[v]; !ok {
+ m[v] = v
+ content += spew.Sprint(v) + ","
+ avl.Put(v)
+ godsavl.Put(v, v)
+ }
+ }
-// if avl.String() != godsavl.String() {
-// t.Error(godsavl.String())
-// t.Error(avl.debugString())
-// t.Error(content, n)
-// break
-// }
-// }
-// }
+ s1 := spew.Sprint(avl.Values())
+ s2 := spew.Sprint(godsavl.Values())
+
+ if s1 != s2 {
+ t.Error(godsavl.String())
+ t.Error(avl.debugString())
+ t.Error(content, n)
+ break
+ }
+ }
+}
func TestGet(t *testing.T) {
avl := New(utils.IntComparator)
@@ -186,7 +147,6 @@ func TestGet(t *testing.T) {
}
func TestRemoveAll(t *testing.T) {
-
ALL:
for c := 0; c < 5000; c++ {
avl := New(utils.IntComparator)
@@ -194,7 +154,7 @@ ALL:
var l []int
m := make(map[int]int)
- for i := 0; len(l) < 100; i++ {
+ for i := 0; len(l) < 10; i++ {
v := randomdata.Number(0, 100000)
if _, ok := m[v]; !ok {
m[v] = v
@@ -204,13 +164,16 @@ ALL:
}
}
- for i := 0; i < 100; i++ {
+ for i := 0; i < 10; i++ {
+
avl.Remove(l[i])
gods.Remove(l[i])
- s1 := spew.Sprint(avl.TraversalDepth(-1))
+
+ s1 := spew.Sprint(avl.Values())
s2 := spew.Sprint(gods.Values())
if s1 != s2 {
t.Error("avl remove error", "avlsize = ", avl.Size())
+ t.Error(avl.root, i, l[i])
t.Error(s1)
t.Error(s2)
break ALL
@@ -245,7 +208,7 @@ ALL:
for i := 0; i < 10; i++ {
avl.Remove(l[i])
gods.Remove(l[i])
- if avl.root != nil && spew.Sprint(gods.Values()) != spew.Sprint(avl.TraversalDepth(-1)) {
+ if avl.root != nil && spew.Sprint(gods.Values()) != spew.Sprint(avl.Values()) {
// if gods.String() != avl.String() && gods.Size() != 0 && avl.size != 0 {
t.Error(src1)
t.Error(src2)
@@ -260,48 +223,26 @@ ALL:
}
}
-// func BenchmarkIterator(b *testing.B) {
-// tree := New(utils.IntComparator)
+func BenchmarkIterator(b *testing.B) {
+ tree := New(utils.IntComparator)
-// l := loadTestData()
-// b.N = len(l)
+ l := loadTestData()
+ b.N = len(l)
-// for _, v := range l {
-// tree.Put(v)
-// }
+ for _, v := range l {
+ tree.Put(v)
+ }
-// b.ResetTimer()
-// b.StartTimer()
-// iter := tree.Iterator()
-// for iter.Next() {
-// }
-// for iter.Prev() {
-// }
-// for iter.Next() {
-// }
-
-// }
-
-// func BenchmarkGodsIterator(b *testing.B) {
-// tree := avltree.NewWithIntComparator()
-
-// l := loadTestData()
-// b.N = len(l)
-
-// for _, v := range l {
-// tree.Put(v, v)
-// }
-
-// b.ResetTimer()
-// b.StartTimer()
-// iter := tree.Iterator()
-// for iter.Next() {
-// }
-// for iter.Prev() {
-// }
-// for iter.Next() {
-// }
-// }
+ b.ResetTimer()
+ b.StartTimer()
+ iter := tree.Iterator()
+ for iter.Next() {
+ }
+ for iter.Prev() {
+ }
+ for iter.Next() {
+ }
+}
func BenchmarkRemove(b *testing.B) {
tree := New(utils.IntComparator)
diff --git a/avlindex/iterator.go b/avlindex/iterator.go
index d15658a..5e525fb 100644
--- a/avlindex/iterator.go
+++ b/avlindex/iterator.go
@@ -5,8 +5,6 @@ import (
)
type Iterator struct {
- op *Tree
-
dir int
up *Node
cur *Node
@@ -15,13 +13,15 @@ type Iterator struct {
}
func initIterator(avltree *Tree) *Iterator {
- iter := &Iterator{op: avltree, tstack: lastack.New()}
+ iter := &Iterator{tstack: lastack.New()}
iter.up = avltree.root
return iter
}
-func NewIterator(tree *Tree) *Iterator {
- return initIterator(tree)
+func NewIterator(n *Node) *Iterator {
+ iter := &Iterator{tstack: lastack.New()}
+ iter.up = n
+ return iter
}
func (iter *Iterator) Value() interface{} {
@@ -46,6 +46,36 @@ func (iter *Iterator) Right() bool {
return false
}
+func GetPrev(cur *Node, idx int) *Node {
+
+ iter := NewIterator(cur)
+ iter.curPushPrevStack(iter.up)
+ iter.up = iter.getPrevUp(iter.up)
+
+ for i := 0; i < idx; i++ {
+
+ if iter.tstack.Size() == 0 {
+ if iter.up == nil {
+ return nil
+ }
+ iter.tstack.Push(iter.up)
+ iter.up = iter.getPrevUp(iter.up)
+ }
+
+ if v, ok := iter.tstack.Pop(); ok {
+ iter.cur = v.(*Node)
+ if i == idx-1 {
+ return iter.cur
+ }
+ iter.curPushPrevStack(iter.cur)
+ } else {
+ return nil
+ }
+ }
+
+ return cur
+}
+
func (iter *Iterator) Prev() (result bool) {
if iter.dir > -1 {
@@ -73,6 +103,35 @@ func (iter *Iterator) Prev() (result bool) {
return false
}
+func GetNext(cur *Node, idx int) *Node {
+
+ iter := NewIterator(cur)
+ iter.curPushNextStack(iter.up)
+ iter.up = iter.getNextUp(iter.up)
+
+ for i := 0; i < idx; i++ {
+
+ if iter.tstack.Size() == 0 {
+ if iter.up == nil {
+ return nil
+ }
+ iter.tstack.Push(iter.up)
+ iter.up = iter.getNextUp(iter.up)
+ }
+
+ if v, ok := iter.tstack.Pop(); ok {
+ iter.cur = v.(*Node)
+ if i == idx-1 {
+ return iter.cur
+ }
+ iter.curPushNextStack(iter.cur)
+ } else {
+ return nil
+ }
+ }
+
+ return cur
+}
func (iter *Iterator) Next() (result bool) {