structure/avlindex/avlindex.go
2019-03-17 01:41:07 +08:00

538 lines
10 KiB
Go

package avlindex
import (
"log"
"github.com/davecgh/go-spew/spew"
"github.com/emirpasic/gods/utils"
)
type Node struct {
children [2]*Node
parent *Node
size int
value interface{}
}
func (n *Node) String() string {
if n == nil {
return "nil"
}
p := "nil"
if n.parent != nil {
p = spew.Sprint(n.parent.value)
}
return spew.Sprint(n.value) + "(" + p + "|" + spew.Sprint(n.size) + ")"
}
type Tree struct {
root *Node
comparator utils.Comparator
count int
}
func New(comparator utils.Comparator) *Tree {
return &Tree{comparator: comparator}
}
func (avl *Tree) String() string {
str := "AVLTree\n"
output(avl.root, "", true, &str)
return str
}
func (avl *Tree) Iterator() *Iterator {
return initIterator(avl)
}
func (avl *Tree) Size() int {
return avl.root.size
}
func (avl *Tree) Remove(key interface{}) *Node {
return nil
}
func (avl *Tree) Get(key interface{}) (interface{}, bool) {
n, ok := avl.GetNode(key)
if ok {
return n.value, true
}
return n, false
}
func (avl *Tree) GetRange(min, max interface{}) []interface{} {
return nil
}
func (avl *Tree) GetAround(key interface{}) (result [3]interface{}) {
an := avl.GetAroundNode(key)
for i, n := range an {
if n != nil {
result[i] = n.value
}
}
return
}
func (avl *Tree) GetAroundNode(value interface{}) (result [3]*Node) {
n := avl.root
for {
if n == nil {
return
}
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:
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")
}
}
}
func (avl *Tree) GetNode(value interface{}) (*Node, bool) {
for n := avl.root; n != nil; {
switch c := avl.comparator(value, n.value); c {
case -1:
n = n.children[0]
case 1:
n = n.children[1]
case 0:
return n, true
default:
panic("Get comparator only is allowed in -1, 0, 1")
}
}
return nil, false
}
func (avl *Tree) Put(value interface{}) {
node := &Node{value: value, size: 1}
if avl.root == nil {
avl.root = node
return
}
cur := avl.root
parent := cur.parent
child := -1
for {
if cur == nil {
parent.children[child] = node
node.parent = parent
fixed := node.parent.parent
for {
switch fsize := getSize(fixed); fsize {
case 3, 5:
log.Println(fsize)
lefts, rigths := getChildrenSize(fixed)
avl.fixPutHeight(fixed, lefts, rigths)
fixed = fixed.parent
default:
return
}
}
}
if cur.size > 7 {
ls, rs := cur.children[0].size, cur.children[1].size
if rs >= ls*2 || ls >= rs*2 {
// ll, lr := getChildrenSize(cur.children[0])
// rl, rr := getChildrenSize(cur.children[1])
avl.fixPutHeight(cur, ls, rs)
}
}
cur.size++
parent = cur
c := avl.comparator(value, cur.value)
child = (c + 2) / 2
cur = cur.children[child]
}
}
func (avl *Tree) debugString() string {
str := "AVLTree\n"
outputfordebug(avl.root, "", true, &str)
return str
}
func (avl *Tree) TraversalBreadth() (result []interface{}) {
result = make([]interface{}, 0, avl.root.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
}
func (avl *Tree) TraversalDepth(leftright int) (result []interface{}) {
result = make([]interface{}, 0, avl.root.size)
if leftright < 0 {
var traverasl func(cur *Node)
traverasl = func(cur *Node) {
if cur == nil {
return
}
traverasl(cur.children[0])
result = append(result, cur.value)
traverasl(cur.children[1])
}
traverasl(avl.root)
} else {
var traverasl func(cur *Node)
traverasl = func(cur *Node) {
if cur == nil {
return
}
traverasl(cur.children[1])
result = append(result, cur.value)
traverasl(cur.children[0])
}
traverasl(avl.root)
}
return
}
func (avl *Tree) lrrotate(cur *Node) {
const l = 1
const r = 0
movparent := cur.children[l]
mov := movparent.children[r]
mov.value, cur.value = cur.value, mov.value //交换值达到, 相对位移
if mov.children[l] != nil {
movparent.children[r] = mov.children[l]
movparent.children[r].parent = movparent
//movparent.children[r].child = l
} else {
movparent.children[r] = nil
}
if mov.children[r] != nil {
mov.children[l] = mov.children[r]
//mov.children[l].child = l
} else {
mov.children[l] = nil
}
if cur.children[r] != nil {
mov.children[r] = cur.children[r]
mov.children[r].parent = mov
} else {
mov.children[r] = nil
}
cur.children[r] = mov
mov.parent = cur
// cur.size = 3
// cur.children[0].size = 1
// cur.children[1].size = 1
movparent.size = getChildrenSumSize(movparent) + 1
mov.size = getChildrenSumSize(mov) + 1
cur.size = getChildrenSumSize(cur) + 1
// mov.height = getMaxChildrenHeight(mov) + 1
// movparent.height = getMaxChildrenHeight(movparent) + 1
// cur.height = getMaxChildrenHeight(cur) + 1
}
func (avl *Tree) rlrotate(cur *Node) {
const l = 0
const r = 1
movparent := cur.children[l]
mov := movparent.children[r]
mov.value, cur.value = cur.value, mov.value //交换值达到, 相对位移
if mov.children[l] != nil {
movparent.children[r] = mov.children[l]
movparent.children[r].parent = movparent
} else {
movparent.children[r] = nil
}
if mov.children[r] != nil {
mov.children[l] = mov.children[r]
} else {
mov.children[l] = nil
}
if cur.children[r] != nil {
mov.children[r] = cur.children[r]
mov.children[r].parent = mov
} else {
mov.children[r] = nil
}
cur.children[r] = mov
mov.parent = cur
movparent.size = getChildrenSumSize(movparent) + 1
mov.size = getChildrenSumSize(mov) + 1
cur.size = getChildrenSumSize(cur) + 1
}
func (avl *Tree) rrotate(cur *Node) {
const l = 0
const r = 1
// 1 right 0 left
mov := cur.children[l]
// lsize, rsize := getChildrenHeight(cur)
// movrsize := getSize(mov.children[r])
mov.value, cur.value = cur.value, mov.value //交换值达到, 相对位移
// mov.children[l]不可能为nil
mov.children[l].parent = cur
cur.children[l] = mov.children[l]
// 解决mov节点孩子转移的问题
if mov.children[r] != nil {
mov.children[l] = mov.children[r]
} else {
mov.children[l] = nil
}
if cur.children[r] != nil {
mov.children[r] = cur.children[r]
mov.children[r].parent = mov
} else {
mov.children[r] = nil
}
// 连接转移后的节点 由于mov只是与cur交换值,parent不变
cur.children[r] = mov
// cur.size = 3
// cur.children[0].size = 1
// cur.children[1].size = 1
mov.size = getChildrenSumSize(mov) + 1
cur.size = getChildrenSumSize(cur) + 1
// cur.height = getMaxChildrenHeight(cur) + 1
}
func (avl *Tree) lrotate(cur *Node) {
const l = 1
const r = 0
// 1 right 0 left
mov := cur.children[l]
// lsize, rsize := getChildrenHeight(cur)
// movrsize := getSize(mov.children[r])
mov.value, cur.value = cur.value, mov.value //交换值达到, 相对位移
// mov.children[l]不可能为nil
mov.children[l].parent = cur
cur.children[l] = mov.children[l]
// 解决mov节点孩子转移的问题
if mov.children[r] != nil {
mov.children[l] = mov.children[r]
} else {
mov.children[l] = nil
}
if cur.children[r] != nil {
mov.children[r] = cur.children[r]
mov.children[r].parent = mov
} else {
mov.children[r] = nil
}
// 连接转移后的节点 由于mov只是与cur交换值,parent不变
cur.children[r] = mov
// cur.size = 3
// cur.children[0].size = 1
// cur.children[1].size = 1
mov.size = getChildrenSumSize(mov) + 1
cur.size = getChildrenSumSize(cur) + 1
}
func getChildrenSumSize(cur *Node) int {
return getSize(cur.children[0]) + getSize(cur.children[1])
}
func getChildrenSize(cur *Node) (int, int) {
return getSize(cur.children[0]), getSize(cur.children[1])
}
func getSize(cur *Node) int {
if cur == nil {
return 0
}
return cur.size
}
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) {
avl.count++
if lefts < rigths {
r := cur.children[1]
rlsize, rrsize := getChildrenSize(r)
if rlsize > rrsize {
avl.lrrotate(cur)
} else {
avl.lrotate(cur)
}
} else {
l := cur.children[0]
llsize, lrsize := getChildrenSize(l)
if lrsize > llsize {
avl.rlrotate(cur)
} else {
avl.rrotate(cur)
}
}
}
func output(node *Node, prefix string, isTail bool, str *string) {
if node.children[1] != nil {
newPrefix := prefix
if isTail {
newPrefix += "│ "
} else {
newPrefix += " "
}
output(node.children[1], newPrefix, false, str)
}
*str += prefix
if isTail {
*str += "└── "
} else {
*str += "┌── "
}
*str += spew.Sprint(node.value) + "\n"
if node.children[0] != nil {
newPrefix := prefix
if isTail {
newPrefix += " "
} else {
newPrefix += "│ "
}
output(node.children[0], newPrefix, true, str)
}
}
func outputfordebug(node *Node, prefix string, isTail bool, str *string) {
if node.children[1] != nil {
newPrefix := prefix
if isTail {
newPrefix += "│ "
} else {
newPrefix += " "
}
outputfordebug(node.children[1], newPrefix, false, str)
}
*str += prefix
if isTail {
*str += "└── "
} else {
*str += "┌── "
}
suffix := "("
parentv := ""
if node.parent == nil {
parentv = "nil"
} else {
parentv = spew.Sprint(node.parent.value)
}
suffix += parentv + "|" + spew.Sprint(node.size) + ")"
*str += spew.Sprint(node.value) + suffix + "\n"
if node.children[0] != nil {
newPrefix := prefix
if isTail {
newPrefix += " "
} else {
newPrefix += "│ "
}
outputfordebug(node.children[0], newPrefix, true, str)
}
}