avl 需要修改Remove返回, 方便操作Iterator

vbtkey/vbtkey.go

@@ -113,7 +113,8 @@ func (tree *Tree) IndexRange(idx1, idx2 int) (result []interface{}, ok bool) { /
 		}
 
 		n := tree.indexNode(idx1)
-		iter := NewIterator(n)
+		tree.iter.SetNode(n)
+		iter := tree.iter
 		result = make([]interface{}, 0, idx1-idx2)
 		for i := idx2; i <= idx1; i++ {
 			if iter.Prev() {
@@ -134,7 +135,8 @@ func (tree *Tree) IndexRange(idx1, idx2 int) (result []interface{}, ok bool) { /
 		}
 
 		if n := tree.indexNode(idx1); n != nil {
-			iter := NewIterator(n)
+			tree.iter.SetNode(n)
+			iter := tree.iter
 			result = make([]interface{}, 0, idx2-idx1)
 			for i := idx1; i <= idx2; i++ {
 				if iter.Next() {
@@ -153,13 +155,13 @@ func (tree *Tree) IndexRange(idx1, idx2 int) (result []interface{}, ok bool) { /
 	return nil, false
 }
 
-func (tree *Tree) RemoveIndex(idx int) bool {
+func (tree *Tree) RemoveIndex(idx int) (*Node, bool) {
 	n := tree.indexNode(idx)
 	if n != nil {
 		tree.removeNode(n)
-		return true
+		return n, true
 	}
-	return false
+	return nil, false
 }
 
 func (tree *Tree) removeNode(n *Node) {
@@ -220,14 +222,14 @@ func (tree *Tree) removeNode(n *Node) {
 	return
 }
 
-func (tree *Tree) Remove(key interface{}) bool {
+func (tree *Tree) Remove(key interface{}) (*Node, bool) {
 
 	if n, ok := tree.GetNode(key); ok {
 		tree.removeNode(n)
-		return true
+		return n, true
 	}
 	// return nil
-	return false
+	return nil, false
 }
 
 // Values 返回先序遍历的值