67 lines
1.1 KiB
Go
67 lines
1.1 KiB
Go
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package avl
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import (
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"log"
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"github.com/emirpasic/gods/stacks/arraystack"
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)
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type Iterator struct {
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op *AVL
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cur *Node
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prevstack *arraystack.Stack
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nextstack *arraystack.Stack
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// curnext *Node
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}
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func initIterator(avltree *AVL) *Iterator {
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iter := &Iterator{op: avltree, prevstack: arraystack.New(), nextstack: arraystack.New()}
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iter.cur = avltree.root
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// iter.nextstack.Push(avltree.root)
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return iter
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}
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func (iter *Iterator) Value() interface{} {
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return iter.cur.value
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}
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func (iter *Iterator) Next() (result bool) {
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if iter.nextstack.Size() == 0 {
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iter.nextstack.Push(iter.cur)
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}
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if v, ok := iter.nextstack.Pop(); ok {
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iter.cur = v.(*Node)
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iter.curPushNextStack(iter.cur)
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log.Println(iter.nextstack.Size())
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return true
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}
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return false
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}
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func (iter *Iterator) curPushNextStack(cur *Node) {
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next := cur.children[0]
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if next != nil {
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iter.nextstack.Push(next)
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for next.children[1] != nil {
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next = next.children[1]
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iter.nextstack.Push(next)
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}
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}
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}
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func (iter *Iterator) Prev() (result bool) {
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if v, ok := iter.nextstack.Pop(); ok {
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iter.cur = v.(*Node)
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iter.curPushNextStack(iter.cur)
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return true
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}
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return false
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}
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