diff --git a/priority_queue/avltree.go b/priority_queue/avltree.go
index 4d80061..db9a559 100644
--- a/priority_queue/avltree.go
+++ b/priority_queue/avltree.go
@@ -22,17 +22,17 @@ func assertTreeImplementation() {
 
 // Tree holds elements of the AVL tree.
 type Tree struct {
-	Root       *ANode           // Root node
+	Root       *AvlNode         // Root node
 	Comparator utils.Comparator // Key comparator
 	size       int              // Total number of keys in the tree
 }
 
-// ANode is a single element within the tree
-type ANode struct {
+// AvlNode is a single element within the tree
+type AvlNode struct {
 	Key      interface{}
 	Value    interface{}
-	Parent   *ANode    // Parent node
-	Children [2]*ANode // Children nodes
+	Parent   *AvlNode    // Parent node
+	Children [2]*AvlNode // Children nodes
 	b        int8
 }
 
@@ -53,8 +53,9 @@ func NewWithStringComparator() *Tree {
 
 // Put inserts node into the tree.
 // Key should adhere to the comparator's type assertion, otherwise method panics.
-func (t *Tree) Put(key interface{}, value interface{}) (bool, *ANode) {
-	return t.put(key, value, nil, &t.Root)
+func (t *Tree) Put(key interface{}, value interface{}) (putNode *AvlNode) {
+	_, putNode = t.put(key, value, nil, &t.Root)
+	return
 }
 
 // Get searches the node in the tree by key and returns its value or nil if key is not found in tree.
@@ -114,13 +115,13 @@ func (t *Tree) Values() []interface{} {
 
 // Left returns the minimum element of the AVL tree
 // or nil if the tree is empty.
-func (t *Tree) Left() *ANode {
+func (t *Tree) Left() *AvlNode {
 	return t.bottom(0)
 }
 
 // Right returns the maximum element of the AVL tree
 // or nil if the tree is empty.
-func (t *Tree) Right() *ANode {
+func (t *Tree) Right() *AvlNode {
 	return t.bottom(1)
 }
 
@@ -132,7 +133,7 @@ func (t *Tree) Right() *ANode {
 // all nodes in the tree is larger than the given node.
 //
 // Key should adhere to the comparator's type assertion, otherwise method panics.
-func (t *Tree) Floor(key interface{}) (floor *ANode, found bool) {
+func (t *Tree) Floor(key interface{}) (floor *AvlNode, found bool) {
 	found = false
 	n := t.Root
 	last := n
@@ -164,7 +165,7 @@ func (t *Tree) Floor(key interface{}) (floor *ANode, found bool) {
 // all nodes in the tree is smaller than the given node.
 //
 // Key should adhere to the comparator's type assertion, otherwise method panics.
-func (t *Tree) Ceiling(key interface{}) (floor *ANode, found bool) {
+func (t *Tree) Ceiling(key interface{}) (floor *AvlNode, found bool) {
 	found = false
 	n := t.Root
 	last := n
@@ -202,15 +203,15 @@ func (t *Tree) String() string {
 	return str
 }
 
-func (n *ANode) String() string {
+func (n *AvlNode) String() string {
 	return fmt.Sprintf("%v", n.Key)
 }
 
-func (t *Tree) put(key interface{}, value interface{}, p *ANode, qp **ANode) (bool, *ANode) {
+func (t *Tree) put(key interface{}, value interface{}, p *AvlNode, qp **AvlNode) (bool, *AvlNode) {
 	q := *qp
 	if q == nil {
 		t.size++
-		*qp = &ANode{Key: key, Value: value, Parent: p}
+		*qp = &AvlNode{Key: key, Value: value, Parent: p}
 		return true, *qp
 	}
 
@@ -230,12 +231,12 @@ func (t *Tree) put(key interface{}, value interface{}, p *ANode, qp **ANode) (bo
 	var fix bool
 	fix, node := t.put(key, value, q, &q.Children[a])
 	if fix {
-		return putFix(int8(c), qp), *qp
+		return putFix(int8(c), qp), node
 	}
-	return false, q
+	return false, node
 }
 
-func (t *Tree) remove(key interface{}, qp **ANode) bool {
+func (t *Tree) remove(key interface{}, qp **AvlNode) bool {
 	q := *qp
 	if q == nil {
 		return false
@@ -271,7 +272,7 @@ func (t *Tree) remove(key interface{}, qp **ANode) bool {
 	return false
 }
 
-func removeMin(qp **ANode, minKey *interface{}, minVal *interface{}) bool {
+func removeMin(qp **AvlNode, minKey *interface{}, minVal *interface{}) bool {
 	q := *qp
 	if q.Children[0] == nil {
 		*minKey = q.Key
@@ -289,7 +290,7 @@ func removeMin(qp **ANode, minKey *interface{}, minVal *interface{}) bool {
 	return false
 }
 
-func putFix(c int8, t **ANode) bool {
+func putFix(c int8, t **AvlNode) bool {
 	s := *t
 	if s.b == 0 {
 		s.b = c
@@ -310,7 +311,7 @@ func putFix(c int8, t **ANode) bool {
 	return false
 }
 
-func removeFix(c int8, t **ANode) bool {
+func removeFix(c int8, t **AvlNode) bool {
 	s := *t
 	if s.b == 0 {
 		s.b = c
@@ -339,14 +340,14 @@ func removeFix(c int8, t **ANode) bool {
 	return true
 }
 
-func singlerot(c int8, s *ANode) *ANode {
+func singlerot(c int8, s *AvlNode) *AvlNode {
 	s.b = 0
 	s = rotate(c, s)
 	s.b = 0
 	return s
 }
 
-func doublerot(c int8, s *ANode) *ANode {
+func doublerot(c int8, s *AvlNode) *AvlNode {
 	a := (c + 1) / 2
 	r := s.Children[a]
 	s.Children[a] = rotate(-c, s.Children[a])
@@ -368,7 +369,7 @@ func doublerot(c int8, s *ANode) *ANode {
 	return p
 }
 
-func rotate(c int8, s *ANode) *ANode {
+func rotate(c int8, s *AvlNode) *AvlNode {
 	a := (c + 1) / 2
 	r := s.Children[a]
 	s.Children[a] = r.Children[a^1]
@@ -381,7 +382,7 @@ func rotate(c int8, s *ANode) *ANode {
 	return r
 }
 
-func (t *Tree) bottom(d int) *ANode {
+func (t *Tree) bottom(d int) *AvlNode {
 	n := t.Root
 	if n == nil {
 		return nil
@@ -395,17 +396,17 @@ func (t *Tree) bottom(d int) *ANode {
 
 // Prev returns the previous element in an inorder
 // walk of the AVL tree.
-func (n *ANode) Prev() *ANode {
+func (n *AvlNode) Prev() *AvlNode {
 	return n.walk1(0)
 }
 
 // Next returns the next element in an inorder
 // walk of the AVL tree.
-func (n *ANode) Next() *ANode {
+func (n *AvlNode) Next() *AvlNode {
 	return n.walk1(1)
 }
 
-func (n *ANode) walk1(a int) *ANode {
+func (n *AvlNode) walk1(a int) *AvlNode {
 	if n == nil {
 		return nil
 	}
@@ -426,7 +427,7 @@ func (n *ANode) walk1(a int) *ANode {
 	return p
 }
 
-func output(node *ANode, prefix string, isTail bool, str *string) {
+func output(node *AvlNode, prefix string, isTail bool, str *string) {
 	if node.Children[1] != nil {
 		newPrefix := prefix
 		if isTail {
diff --git a/priority_queue/iterator.go b/priority_queue/iterator.go
index da9d9cb..42570c5 100644
--- a/priority_queue/iterator.go
+++ b/priority_queue/iterator.go
@@ -13,7 +13,7 @@ func assertIteratorImplementation() {
 // Iterator holding the iterator's state
 type Iterator struct {
 	tree     *Tree
-	node     *ANode
+	node     *AvlNode
 	position position
 }
 
diff --git a/priority_queue/priority_queue_test.go b/priority_queue/priority_queue_test.go
index 2521427..2d8ea31 100644
--- a/priority_queue/priority_queue_test.go
+++ b/priority_queue/priority_queue_test.go
@@ -78,10 +78,13 @@ import (
 
 func TestAVL(t *testing.T) {
 	avl := NewWithIntComparator()
-	for i := 0; i < 100; i++ {
+	for i := 0; i < 100000; i++ {
 		v := randomdata.Number(0, 100)
-		ok, n := avl.Put(v, v)
-		t.Error(v, ok, n)
+		n := avl.Put(v, v)
+		if v != n.Value.(int) {
+			t.Error(v, n)
+		}
+
 	}
 	t.Error(avl.Values())
 	f, ok := avl.Ceiling(1000)