diff --git a/collections/ArrayList.go b/collections/ArrayList.go
index d804f27..933e73f 100644
--- a/collections/ArrayList.go
+++ b/collections/ArrayList.go
@@ -5,10 +5,16 @@ import (
 	"github.com/tursom/GoCollections/lang"
 )
 
-type ArrayList[T lang.Object] struct {
-	lang.BaseObject
-	array []T
-}
+type (
+	ArrayList[T lang.Object] struct {
+		lang.BaseObject
+		array []T
+	}
+	arrayListIterator[T lang.Object] struct {
+		arrayList *ArrayList[T]
+		index     int
+	}
+)
 
 func NewArrayList[T lang.Object]() *ArrayList[T] {
 	return NewArrayListByCapacity[T](16)
@@ -137,11 +143,6 @@ func (a *ArrayList[T]) RemoveLast() (T, exceptions.Exception) {
 	return v, a.RemoveAt(a.Size() - 1)
 }
 
-type arrayListIterator[T lang.Object] struct {
-	arrayList *ArrayList[T]
-	index     int
-}
-
 func (a *arrayListIterator[T]) HasNext() bool {
 	return a.index < a.arrayList.Size()
 }
diff --git a/collections/Collection.go b/collections/Collection.go
index eec87b4..79108e6 100644
--- a/collections/Collection.go
+++ b/collections/Collection.go
@@ -9,7 +9,7 @@ import (
 
 type (
 	Collection[T any] interface {
-		Iterator() Iterator[T]
+		Iterable[T]
 		Size() int
 		IsEmpty() bool
 		Contains(element T) bool
@@ -17,13 +17,9 @@ type (
 	}
 
 	MutableCollection[T any] interface {
-		Iterator() Iterator[T]
-		Size() int
-		IsEmpty() bool
-		Contains(element T) bool
-		ContainsAll(c Collection[T]) bool
+		Collection[T]
+		MutableIterable[T]
 
-		MutableIterator() MutableIterator[T]
 		Add(element T) bool
 		Remove(element T) exceptions.Exception
 		AddAll(c Collection[T]) bool
@@ -33,33 +29,15 @@ type (
 	}
 
 	List[T any] interface {
-		Iterator() Iterator[T]
-		Size() int
-		IsEmpty() bool
-		Contains(element T) bool
-		ContainsAll(c Collection[T]) bool
+		Collection[T]
 
 		Get(index int) (T, exceptions.Exception)
 		SubList(from, to int) List[T]
 	}
 
 	MutableList[T any] interface {
-		Iterator() Iterator[T]
-		Size() int
-		IsEmpty() bool
-		Contains(element T) bool
-		ContainsAll(c Collection[T]) bool
-
-		MutableIterator() MutableIterator[T]
-		Add(element T) bool
-		Remove(element T) exceptions.Exception
-		AddAll(c Collection[T]) bool
-		RemoveAll(c Collection[T]) bool
-		RetainAll(c Collection[T]) bool
-		Clear()
-
-		Get(index int) (T, exceptions.Exception)
-		SubList(from, to int) List[T]
+		List[T]
+		MutableCollection[T]
 
 		Set(index int, element T) exceptions.Exception
 		AddAtIndex(index int, element T) bool
diff --git a/collections/ConcurrentLinkedQueue.go b/collections/ConcurrentLinkedQueue.go
index b32ee3f..7bd6103 100644
--- a/collections/ConcurrentLinkedQueue.go
+++ b/collections/ConcurrentLinkedQueue.go
@@ -3,157 +3,166 @@ package collections
 import (
 	"github.com/tursom/GoCollections/exceptions"
 	"github.com/tursom/GoCollections/lang"
-	"sync/atomic"
-	"unsafe"
+	"github.com/tursom/GoCollections/lang/atomic"
 )
 
-type ConcurrentLinkedQueue[T lang.Object] struct {
-	lang.BaseObject
-	head *concurrentLinkedQueueNode[T]
-}
+type (
+	ConcurrentLinkedQueueNode[T lang.Object] interface {
+		Get() (T, exceptions.Exception)
+		Remove() exceptions.Exception
+		RemoveAndGet() (T, exceptions.Exception)
+	}
 
-func (c *ConcurrentLinkedQueue[T]) String() string {
-	return String[T](c)
-}
+	ConcurrentLinkedQueue[T lang.Object] struct {
+		lang.BaseObject
+		ConcurrentLinkedStack[T]
+		end *concurrentLinkedStackNode[T]
+	}
 
-type concurrentLinkedQueueNode[T any] struct {
-	value T
-	prev  *concurrentLinkedQueueNode[T]
-	next  *concurrentLinkedQueueNode[T]
-}
+	concurrentLinkedQueueIterator[T lang.Object] struct {
+		node  *concurrentLinkedStackNode[T]
+		queue *ConcurrentLinkedQueue[T]
+	}
+)
 
-type concurrentLinkedQueueIterator[T any] struct {
-	head *concurrentLinkedQueueNode[T]
-	node *concurrentLinkedQueueNode[T]
+func (q *ConcurrentLinkedQueue[T]) String() string {
+	return String[T](q)
 }
 
 func NewConcurrentLinkedQueue[T lang.Object]() *ConcurrentLinkedQueue[T] {
-	head := &concurrentLinkedQueueNode[T]{}
-	head.prev = head
-	head.next = head
-	return &ConcurrentLinkedQueue[T]{lang.NewBaseObject(), head}
+	return &ConcurrentLinkedQueue[T]{}
 }
 
-func (c *ConcurrentLinkedQueue[T]) Iterator() Iterator[T] {
-	return c.MutableIterator()
+func (q *ConcurrentLinkedQueue[T]) Iterator() Iterator[T] {
+	return q.MutableIterator()
 }
 
-func (c *ConcurrentLinkedQueue[T]) Push(element T) exceptions.Exception {
-	newNode := &concurrentLinkedQueueNode[T]{element, c.head.prev, c.head}
-	p := (*unsafe.Pointer)(unsafe.Pointer(&c.head.prev))
-	for !atomic.CompareAndSwapPointer(p, unsafe.Pointer(&*newNode.prev), unsafe.Pointer(newNode)) {
-		newNode.prev = c.head.prev
+func (q *ConcurrentLinkedQueue[T]) Offer(element T) exceptions.Exception {
+	_, err := q.offerAndGetNode(element)
+	return err
+}
+
+func (q *ConcurrentLinkedQueue[T]) OfferAndGetNode(element T) (ConcurrentLinkedQueueNode[T], exceptions.Exception) {
+	newNode, err := q.offerAndGetNode(element)
+	if err != nil {
+		return nil, err
 	}
-	atomic.CompareAndSwapPointer(
-		(*unsafe.Pointer)(unsafe.Pointer(&newNode.prev.next)),
-		unsafe.Pointer(&*c.head),
-		unsafe.Pointer(newNode),
-	)
-	return nil
+	return &concurrentLinkedQueueIterator[T]{queue: q, node: newNode}, nil
 }
 
-func (c *ConcurrentLinkedQueue[T]) Offer() (T, exceptions.Exception) {
-	next := c.head.next
-	if next == c.head {
-		return lang.Nil[T](), exceptions.NewIndexOutOfBound("", nil)
+func (q *ConcurrentLinkedQueue[T]) offerAndGetNode(element T) (*concurrentLinkedStackNode[T], exceptions.Exception) {
+	newNode := &concurrentLinkedStackNode[T]{value: element}
+	q.size.Add(1)
+
+	var next **concurrentLinkedStackNode[T]
+	ref := q.end
+	switch {
+	case ref == nil:
+		next = &q.head
+	default:
+		next = &ref.next
 	}
-
-	p := (*unsafe.Pointer)(unsafe.Pointer(&next.next.prev))
-
-	if !next.removeNode(p) {
-		next = c.head.next
-		p = (*unsafe.Pointer)(unsafe.Pointer(&next.prev))
-		if next == nil {
-			return lang.Nil[T](), exceptions.NewIndexOutOfBound("", nil)
+	for !atomic.CompareAndSwapPointer(next, nil, newNode) {
+		if ref == nil || ref.next == nil {
+			next = &q.head
+			ref = q.head
+		} else {
+			for ref.next != nil {
+				ref = ref.next
+			}
+			next = &ref.next
 		}
 	}
-
-	return next.value, nil
+	q.end = newNode
+	return newNode, nil
 }
 
-func (node *concurrentLinkedQueueNode[T]) removeNode(p *unsafe.Pointer) bool {
-	if p == nil {
-		p = (*unsafe.Pointer)(unsafe.Pointer(&node.next.prev))
-	}
-	if !atomic.CompareAndSwapPointer(p, unsafe.Pointer(node), unsafe.Pointer(&*node.prev)) {
-		return false
-	}
-	atomic.CompareAndSwapPointer(
-		(*unsafe.Pointer)(unsafe.Pointer(&node.prev.next)),
-		unsafe.Pointer(node),
-		unsafe.Pointer(&*node.next),
-	)
-	return true
+func (q *ConcurrentLinkedQueue[T]) Poll() (T, exceptions.Exception) {
+	return q.Pop()
 }
 
-func (c *ConcurrentLinkedQueue[T]) MutableIterator() MutableIterator[T] {
-	return &concurrentLinkedQueueIterator[T]{c.head, c.head}
+func (q *ConcurrentLinkedQueue[T]) MutableIterator() MutableIterator[T] {
+	return &concurrentLinkedQueueIterator[T]{node: q.head}
 }
 
-func (c *concurrentLinkedQueueIterator[T]) HasNext() bool {
-	return c.node.next != c.head
+func (q *ConcurrentLinkedQueue[T]) Size() int {
+	return int(q.size.Load())
 }
 
-func (c *concurrentLinkedQueueIterator[T]) Next() (T, exceptions.Exception) {
-	c.node = c.node.next
-	if c.node == c.head {
-		return lang.Nil[T](), exceptions.NewIndexOutOfBound("", nil)
-	}
-	return c.node.value, nil
+func (q *ConcurrentLinkedQueue[T]) IsEmpty() bool {
+	return q.head == nil
 }
 
-func (c *concurrentLinkedQueueIterator[T]) Remove() exceptions.Exception {
-	if c.node == c.head {
-		return exceptions.NewIndexOutOfBound("", nil)
-	}
-	c.node.removeNode(nil)
-	c.node = c.node.prev
-	return nil
+func (q *ConcurrentLinkedQueue[T]) Contains(element T) bool {
+	return Contains[T](q, element)
 }
 
-func (c *ConcurrentLinkedQueue[T]) Size() int {
-	size, err := Size[T](c)
-	exceptions.Print(err)
-	return size
+func (q *ConcurrentLinkedQueue[T]) ContainsAll(collection Collection[T]) bool {
+	return ContainsAll[T](q, collection)
 }
 
-func (c *ConcurrentLinkedQueue[T]) IsEmpty() bool {
-	return c.head.next == c.head
-}
-
-func (c *ConcurrentLinkedQueue[T]) Contains(element T) bool {
-	return Contains[T](c, element)
-}
-
-func (c *ConcurrentLinkedQueue[T]) ContainsAll(collection Collection[T]) bool {
-	return ContainsAll[T](c, collection)
-}
-
-func (c *ConcurrentLinkedQueue[T]) Add(element T) bool {
-	exception := c.Push(element)
+func (q *ConcurrentLinkedQueue[T]) Add(element T) bool {
+	exception := q.Push(element)
 	exceptions.Print(exception)
 	return exception == nil
 }
 
-func (c *ConcurrentLinkedQueue[T]) Remove(element T) exceptions.Exception {
-	return Remove[T](c, element)
+func (q *ConcurrentLinkedQueue[T]) Remove(element T) exceptions.Exception {
+	return Remove[T](q, element)
 }
 
-func (c *ConcurrentLinkedQueue[T]) AddAll(collection Collection[T]) bool {
-	return AddAll[T](c, collection)
+func (q *ConcurrentLinkedQueue[T]) AddAll(collection Collection[T]) bool {
+	return AddAll[T](q, collection)
 }
 
-func (c *ConcurrentLinkedQueue[T]) RemoveAll(collection Collection[T]) bool {
-	return RemoveAll[T](c, collection)
+func (q *ConcurrentLinkedQueue[T]) RemoveAll(collection Collection[T]) bool {
+	return RemoveAll[T](q, collection)
 }
 
-func (c *ConcurrentLinkedQueue[T]) RetainAll(collection Collection[T]) bool {
-	return RetainAll[T](c, collection)
+func (q *ConcurrentLinkedQueue[T]) RetainAll(collection Collection[T]) bool {
+	return RetainAll[T](q, collection)
 }
 
-func (c *ConcurrentLinkedQueue[T]) Clear() {
-	head := &concurrentLinkedQueueNode[T]{}
-	head.prev = head
-	head.next = head
-	c.head = head
+func (q *ConcurrentLinkedQueue[T]) Clear() {
+	q.head = nil
+	q.end = nil
+	q.size.Store(0)
+}
+
+func (i *concurrentLinkedQueueIterator[T]) HasNext() bool {
+	for i.node != nil && i.node.deleted {
+		i.node = i.node.next
+	}
+	return i.node != nil
+}
+
+func (i *concurrentLinkedQueueIterator[T]) Next() (T, exceptions.Exception) {
+	value, err := i.Get()
+	i.node = i.node.next
+	for i.node != nil && i.node.deleted {
+		i.node = i.node.next
+	}
+	return value, err
+}
+
+func (i *concurrentLinkedQueueIterator[T]) Get() (T, exceptions.Exception) {
+	return (*i.node).value, nil
+}
+
+func (i *concurrentLinkedQueueIterator[T]) Remove() exceptions.Exception {
+	_, err := i.RemoveAndGet()
+	return err
+}
+
+func (i *concurrentLinkedQueueIterator[T]) RemoveAndGet() (T, exceptions.Exception) {
+	if i.node == nil {
+		return lang.Nil[T](), nil
+	}
+	load := i.node
+	load.deleted = true
+	i.queue.size.Add(-1)
+	i.queue.deleted.Add(1)
+	i.queue.CleanDeleted()
+	i.node = load.next
+	return load.value, nil
 }
diff --git a/collections/ConcurrentLinkedQueue_test.go b/collections/ConcurrentLinkedQueue_test.go
new file mode 100644
index 0000000..8259db1
--- /dev/null
+++ b/collections/ConcurrentLinkedQueue_test.go
@@ -0,0 +1,97 @@
+package collections
+
+import (
+	"fmt"
+	"github.com/tursom/GoCollections/exceptions"
+	"github.com/tursom/GoCollections/lang"
+	"sync"
+	"testing"
+	"time"
+	"unsafe"
+)
+
+type data struct {
+	lang.BaseObject
+	id    int
+	index int
+}
+
+func (d *data) String() string {
+	return fmt.Sprintf("(%d,%d)", d.id, d.index)
+}
+
+func TestConcurrentLinkedQueue_NodeSize(t *testing.T) {
+	fmt.Println(unsafe.Alignof(concurrentLinkedStackNode[*data]{}))
+	fmt.Println(unsafe.Sizeof(concurrentLinkedStackNode[*data]{}))
+}
+
+func TestConcurrentLinkedQueue_Push(t *testing.T) {
+	queue := NewConcurrentLinkedQueue[*data]()
+	cond := sync.WaitGroup{}
+	cond.Add(1)
+	for i := 0; i < 10; i++ {
+		id := i
+		go func() {
+			cond.Wait()
+			for i := 0; i < 100; i++ {
+				_ = queue.Offer(&data{id: id, index: i})
+			}
+		}()
+	}
+	time.Sleep(time.Second)
+	cond.Done()
+	time.Sleep(time.Second)
+	fmt.Println(queue)
+}
+
+func TestConcurrentLinkedQueue_ThreadSafe(t *testing.T) {
+	times := 400000
+	queue := NewConcurrentLinkedQueue[*data]()
+	for i := 0; i < 100; i++ {
+		id := i
+		go func() {
+			//nodes := make([]ConcurrentLinkedQueueNode[*data], 0)
+			for j := 0; j < times; j++ {
+				_ = queue.Offer(&data{id: id, index: j})
+				//node, _ := queue.OfferAndGetNode(&data{id: id, index: j})
+				//nodes = append(nodes, node)
+				//fmt.Println(queue)
+			}
+			//time.Sleep(time.Second * 1)
+			fmt.Println(queue.Size())
+			//for _, node := range nodes {
+			//	exceptions.Exec0r0(node.Remove)
+			//}
+			for j := 0; j < times; j++ {
+				offer, _ := queue.Poll()
+				if offer == nil {
+					panic("offer is nil")
+				}
+			}
+		}()
+	}
+
+	time.Sleep(time.Second * 10)
+	if queue.Size() != 0 {
+		t.Fatalf(fmt.Sprintf("queue remain %d element, is not thread safe", queue.Size()))
+	}
+	//for !queue.IsEmpty() {
+	//	fmt.Println(queue.Offer())
+	//}
+}
+
+func Test_concurrentLinkedQueueIterator_Remove(t *testing.T) {
+	queue := NewConcurrentLinkedQueue[lang.Int]()
+	nodes := make([]ConcurrentLinkedQueueNode[lang.Int], 0)
+	for i := 0; i < 1000; i++ {
+		node, _ := queue.OfferAndGetNode(lang.Int(i))
+		nodes = append(nodes, node)
+		//fmt.Println(queue)
+	}
+	for _, node := range nodes {
+		fmt.Println(exceptions.Exec0r1(node.RemoveAndGet))
+	}
+	if queue.Size() != 0 {
+		t.Fatalf(fmt.Sprintf("queue remain %d element, is not thread safe", queue.Size()))
+	}
+}
diff --git a/collections/ConcurrentLinkedStack.go b/collections/ConcurrentLinkedStack.go
index 77a8111..d004484 100644
--- a/collections/ConcurrentLinkedStack.go
+++ b/collections/ConcurrentLinkedStack.go
@@ -3,89 +3,146 @@ package collections
 import (
 	"github.com/tursom/GoCollections/exceptions"
 	"github.com/tursom/GoCollections/lang"
-	"sync/atomic"
-	"unsafe"
+	"github.com/tursom/GoCollections/lang/atomic"
 )
 
-type ConcurrentLinkedStack[T any] struct {
-	lang.BaseObject
-	head *concurrentLinkedStackNode[T]
-	p    *unsafe.Pointer
-}
-
-func (c ConcurrentLinkedStack[T]) String() string {
-	return String[T](c)
-}
-
-type concurrentLinkedStackNode[T any] struct {
-	value T
-	next  *concurrentLinkedStackNode[T]
-}
-
-type concurrentLinkedStackIterator[T any] struct {
-	node *concurrentLinkedStackNode[T]
-	prev *concurrentLinkedStackNode[T]
-}
-
-func NewConcurrentLinkedStack[T any]() *ConcurrentLinkedStack[T] {
-	head := &concurrentLinkedStackNode[T]{}
-	return &ConcurrentLinkedStack[T]{lang.NewBaseObject(), head, (*unsafe.Pointer)(unsafe.Pointer(&head.next))}
-}
-
-func (c ConcurrentLinkedStack[T]) Iterator() Iterator[T] {
-	return c.MutableIterator()
-}
-
-func (c *ConcurrentLinkedStack[T]) Push(element T) exceptions.Exception {
-	newNode := &concurrentLinkedStackNode[T]{element, c.head.next}
-	np := unsafe.Pointer(newNode)
-	for !atomic.CompareAndSwapPointer(c.p, unsafe.Pointer(&*newNode.next), np) {
+type (
+	ConcurrentLinkedStack[T lang.Object] struct {
+		lang.BaseObject
+		size    atomic.Int32
+		deleted atomic.Int32
+		head    *concurrentLinkedStackNode[T]
 	}
+
+	concurrentLinkedStackNode[T any] struct {
+		deleted bool
+		next    *concurrentLinkedStackNode[T]
+		value   T
+	}
+
+	concurrentLinkedStackIterator[T lang.Object] struct {
+		node  *concurrentLinkedStackNode[T]
+		stack *ConcurrentLinkedStack[T]
+	}
+)
+
+func (s *ConcurrentLinkedStack[T]) String() string {
+	return String[T](s)
+}
+
+func NewConcurrentLinkedStack[T lang.Object]() *ConcurrentLinkedStack[T] {
+	return &ConcurrentLinkedStack[T]{}
+}
+
+func (s *ConcurrentLinkedStack[T]) Iterator() Iterator[T] {
+	return s.MutableIterator()
+}
+
+func (s *ConcurrentLinkedStack[T]) Push(element T) exceptions.Exception {
+	newNode := &concurrentLinkedStackNode[T]{value: element, next: s.head}
+	for !atomic.CompareAndSwapPointer(&s.head, newNode.next, newNode) {
+		newNode.next = s.head
+	}
+	s.size.Add(1)
 	return nil
 }
 
-func (c *ConcurrentLinkedStack[T]) Pop() (T, exceptions.Exception) {
-	next := c.head.next
-	if next == nil {
+func (s *ConcurrentLinkedStack[T]) Pop() (T, exceptions.Exception) {
+	node := s.head
+	for node != nil && (!atomic.CompareAndSwapPointer(&s.head, node, node.next) || node.deleted) {
+		node = s.head
+	}
+	if node == nil {
 		return lang.Nil[T](), exceptions.NewIndexOutOfBound("", nil)
 	}
 
-	p := (*unsafe.Pointer)(unsafe.Pointer(&c.head.next))
+	s.size.Add(-1)
+	return node.value, nil
+}
 
-	if !atomic.CompareAndSwapPointer(p, unsafe.Pointer(&*next), unsafe.Pointer(&*next.next)) {
-		next = c.head.next
-		if next == nil {
-			return lang.Nil[T](), exceptions.NewIndexOutOfBound("", nil)
+func (s *ConcurrentLinkedStack[T]) CleanDeleted() {
+	if s.deleted.Load() <= s.size.Load() {
+		return
+	}
+	s.deleted.Store(0)
+	node := &s.head
+	for node != nil && *node != nil {
+		if (*node).deleted {
+			atomic.CompareAndSwapPointer(node, *node, (*node).next)
+		} else {
+			node = &(*node).next
 		}
 	}
-
-	return next.value, nil
 }
 
-func (c *ConcurrentLinkedStack[T]) MutableIterator() MutableIterator[T] {
-	return &concurrentLinkedStackIterator[T]{c.head, nil}
+func (s *ConcurrentLinkedStack[T]) Size() int {
+	return int(s.size.Load())
 }
 
-func (c *concurrentLinkedStackIterator[T]) HasNext() bool {
-	return c.node.next != nil
+func (s *ConcurrentLinkedStack[T]) IsEmpty() bool {
+	return s.head == nil
 }
 
-func (c *concurrentLinkedStackIterator[T]) Next() (T, exceptions.Exception) {
-	c.prev = c.node
-	c.node = c.node.next
-	if c.node == nil {
+func (s *ConcurrentLinkedStack[T]) Contains(element T) bool {
+	return Contains[T](s, element)
+}
+
+func (s *ConcurrentLinkedStack[T]) ContainsAll(c Collection[T]) bool {
+	return ContainsAll[T](s, c)
+}
+
+func (s *ConcurrentLinkedStack[T]) Add(element T) bool {
+	exception := s.Push(element)
+	exceptions.Print(exception)
+	return exception == nil
+}
+
+func (s *ConcurrentLinkedStack[T]) Remove(element T) exceptions.Exception {
+	return Remove[T](s, element)
+}
+
+func (s *ConcurrentLinkedStack[T]) AddAll(c Collection[T]) bool {
+	return AddAll[T](s, c)
+}
+
+func (s *ConcurrentLinkedStack[T]) RemoveAll(c Collection[T]) bool {
+	return RemoveAll[T](s, c)
+}
+
+func (s *ConcurrentLinkedStack[T]) RetainAll(c Collection[T]) bool {
+	return RetainAll[T](s, c)
+}
+
+func (s *ConcurrentLinkedStack[T]) Clear() {
+	s.head = nil
+	s.size.Store(0)
+}
+
+func (s *ConcurrentLinkedStack[T]) MutableIterator() MutableIterator[T] {
+	return &concurrentLinkedStackIterator[T]{s.head, nil}
+}
+
+func (i *concurrentLinkedStackIterator[T]) HasNext() bool {
+	return i.node.next != nil
+}
+
+func (i *concurrentLinkedStackIterator[T]) Next() (T, exceptions.Exception) {
+	if i.node == nil {
 		return lang.Nil[T](), exceptions.NewIndexOutOfBound("", nil)
 	}
-	return c.node.value, nil
+	value := i.node.value
+	i.node = i.node.next
+	return value, nil
 }
 
-func (c *concurrentLinkedStackIterator[T]) Remove() exceptions.Exception {
-	if c.node == nil {
+func (i *concurrentLinkedStackIterator[T]) Remove() exceptions.Exception {
+	if i.node == nil {
 		return exceptions.NewIndexOutOfBound("", nil)
 	}
-	next := c.node.next
-
-	p := (*unsafe.Pointer)(unsafe.Pointer(&c.prev.next))
-	atomic.CompareAndSwapPointer(p, unsafe.Pointer(&*c.node), unsafe.Pointer(&*next))
+	i.node.deleted = true
+	i.node = i.node.next
+	i.stack.size.Add(-1)
+	i.stack.deleted.Add(1)
+	i.stack.CleanDeleted()
 	return nil
 }
diff --git a/collections/CopyOnWriteList.go b/collections/CopyOnWriteList.go
new file mode 100644
index 0000000..074ceb4
--- /dev/null
+++ b/collections/CopyOnWriteList.go
@@ -0,0 +1,126 @@
+package collections
+
+import (
+	"github.com/tursom/GoCollections/exceptions"
+	"github.com/tursom/GoCollections/lang"
+)
+
+type (
+	CopyOnWriteList[E lang.Object] struct {
+		lang.BaseObject
+		arr []E
+	}
+
+	copyOnWriteListIterator[E lang.Object] struct {
+		lang.BaseObject
+		list  *CopyOnWriteList[E]
+		arr   []E
+		index int
+	}
+)
+
+func (l *CopyOnWriteList[E]) Iterator() Iterator[E] {
+	return l.MutableIterator()
+}
+
+func (l *CopyOnWriteList[E]) Size() int {
+	return len(l.arr)
+}
+
+func (l *CopyOnWriteList[E]) IsEmpty() bool {
+	return l.Size() == 0
+}
+
+func (l *CopyOnWriteList[E]) Contains(element E) bool {
+	return Contains[E](l, element)
+}
+
+func (l *CopyOnWriteList[E]) ContainsAll(c Collection[E]) bool {
+	return ContainsAll[E](l, c)
+}
+
+func (l *CopyOnWriteList[E]) MutableIterator() MutableIterator[E] {
+	return &copyOnWriteListIterator[E]{
+		list:  l,
+		arr:   l.arr,
+		index: 0,
+	}
+}
+
+func (l *CopyOnWriteList[E]) Add(element E) bool {
+	l.arr = append(l.arr, element)
+	return true
+}
+
+func (l *CopyOnWriteList[E]) Remove(element E) exceptions.Exception {
+	return Remove[E](l, element)
+}
+
+func (l *CopyOnWriteList[E]) AddAll(c Collection[E]) bool {
+	_ = Loop[E](c, func(element E) exceptions.Exception {
+		l.arr = append(l.arr, element)
+		return nil
+	})
+	return true
+}
+
+func (l *CopyOnWriteList[E]) RemoveAll(c Collection[E]) bool {
+	return RemoveAll[E](l, c)
+}
+
+func (l *CopyOnWriteList[E]) RetainAll(c Collection[E]) bool {
+	return RetainAll[E](l, c)
+}
+
+func (l *CopyOnWriteList[E]) Clear() {
+	l.arr = make([]E, 0)
+}
+
+func (l *CopyOnWriteList[E]) Get(index int) (E, exceptions.Exception) {
+	if index < 0 || index >= l.Size() {
+		return lang.Nil[E](), exceptions.NewIndexOutOfBound("", nil)
+	}
+	return l.arr[index], nil
+}
+
+func (l *CopyOnWriteList[E]) SubList(from, to int) List[E] {
+	return l.SubList(from, to)
+}
+
+func (l *CopyOnWriteList[E]) Set(index int, element E) exceptions.Exception {
+	if index < 0 || index >= l.Size() {
+		return exceptions.NewIndexOutOfBound("", nil)
+	}
+	l.arr[index] = element
+	return nil
+}
+
+func (l *CopyOnWriteList[E]) AddAtIndex(index int, element E) bool {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (l *CopyOnWriteList[E]) RemoveAt(index int) exceptions.Exception {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (l *CopyOnWriteList[E]) SubMutableList(from, to int) MutableList[E] {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (c *copyOnWriteListIterator[E]) HasNext() bool {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (c *copyOnWriteListIterator[E]) Next() (E, exceptions.Exception) {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (c *copyOnWriteListIterator[E]) Remove() exceptions.Exception {
+	//TODO implement me
+	panic("implement me")
+}
diff --git a/collections/Iterable.go b/collections/Iterable.go
index 33d971a..a2e30e7 100644
--- a/collections/Iterable.go
+++ b/collections/Iterable.go
@@ -13,13 +13,12 @@ type Iterable[T any] interface {
 }
 
 type MutableIterator[T any] interface {
-	HasNext() bool
-	Next() (T, exceptions.Exception)
+	Iterator[T]
 	Remove() exceptions.Exception
 }
 
 type MutableIterable[T any] interface {
-	Iterator() Iterator[T]
+	Iterable[T]
 	MutableIterator() MutableIterator[T]
 }
 
diff --git a/collections/Queue.go b/collections/Queue.go
index e0c31e4..fa03da5 100644
--- a/collections/Queue.go
+++ b/collections/Queue.go
@@ -6,11 +6,8 @@ import (
 )
 
 type Queue[T lang.Object] interface {
-	// Iterator MutableIterable
-	Iterator() Iterator[T]
-	// MutableIterator MutableIterable
-	MutableIterator() *linkedListIterator[T]
+	MutableIterable[T]
 
-	Push(element T) exceptions.Exception
-	Offer() (T, exceptions.Exception)
+	Offer(element T) exceptions.Exception
+	Poll() (T, exceptions.Exception)
 }
diff --git a/collections/Stack.go b/collections/Stack.go
index ba0a6a9..b326e1c 100644
--- a/collections/Stack.go
+++ b/collections/Stack.go
@@ -3,10 +3,7 @@ package collections
 import "github.com/tursom/GoCollections/exceptions"
 
 type Stack[T any] interface {
-	// Iterator MutableIterable
-	Iterator() Iterator[T]
-	// MutableIterator MutableIterable
-	MutableIterator() MutableIterator[T]
+	MutableIterable[T]
 
 	Push(element T) exceptions.Exception
 	Pop() (T, exceptions.Exception)
diff --git a/exceptions/Exception.go b/exceptions/Exception.go
index 01037e4..fde6498 100644
--- a/exceptions/Exception.go
+++ b/exceptions/Exception.go
@@ -10,6 +10,7 @@ import (
 type Exception interface {
 	Cause() Exception
 	Error() string
+	ErrorMessage() string
 	StackTrace() []StackTrace
 	PrintStackTrace()
 	PrintStackTraceTo(writer io.Writer)
@@ -46,7 +47,7 @@ func BuildStackTraceByArray(builder *strings.Builder, trace []StackTrace) {
 }
 
 func BuildStackTrace(builder *strings.Builder, e Exception, exceptionMsg string) {
-	builder.WriteString(fmt.Sprintln(exceptionMsg, e.Error()))
+	builder.WriteString(fmt.Sprintln(exceptionMsg, e.ErrorMessage()))
 	if e.StackTrace() == nil {
 		return
 	}
diff --git a/exceptions/RuntimeException.go b/exceptions/RuntimeException.go
index fb98eeb..15af254 100644
--- a/exceptions/RuntimeException.go
+++ b/exceptions/RuntimeException.go
@@ -60,6 +60,10 @@ func (o RuntimeException) Error() string {
 	return builder.String()
 }
 
+func (o RuntimeException) ErrorMessage() string {
+	return o.exceptionMessage
+}
+
 func (o RuntimeException) StackTrace() []StackTrace {
 	return o.stackTrace
 }
diff --git a/lang/Lang.go b/lang/Lang.go
index 7e47d69..b37a3f4 100644
--- a/lang/Lang.go
+++ b/lang/Lang.go
@@ -32,10 +32,10 @@ func Cast[T any](v any) T {
 	}
 }
 
-func ForceCast[T any](v *any) T {
+func ForceCast[T any](v unsafe.Pointer) T {
 	if v == nil {
 		return Nil[T]()
 	} else {
-		return Cast[T](unsafe.Pointer(v))
+		return Cast[T](v)
 	}
 }
diff --git a/lang/atomic/Bool.go b/lang/atomic/Bool.go
new file mode 100644
index 0000000..f8d6663
--- /dev/null
+++ b/lang/atomic/Bool.go
@@ -0,0 +1,37 @@
+package atomic
+
+type Bool struct {
+	i Int32
+}
+
+func (v *Bool) Load() (val bool) {
+	return v.i.Load() != 0
+}
+
+func (v *Bool) Store(val bool) {
+	if val {
+		v.i.Store(1)
+	} else {
+		v.i.Store(0)
+	}
+}
+
+func (v *Bool) Swap(new bool) (old bool) {
+	n := int32(0)
+	if new {
+		n = 1
+	}
+	return v.i.Swap(n) != 0
+}
+
+func (v *Bool) CompareAndSwap(old, new bool) (swapped bool) {
+	o := int32(0)
+	if old {
+		o = 1
+	}
+	n := int32(0)
+	if new {
+		n = 1
+	}
+	return v.i.CompareAndSwap(o, n)
+}
diff --git a/lang/atomic/Int32.go b/lang/atomic/Int32.go
new file mode 100644
index 0000000..b45c4f3
--- /dev/null
+++ b/lang/atomic/Int32.go
@@ -0,0 +1,29 @@
+package atomic
+
+import (
+	"sync/atomic"
+)
+
+type Int32 struct {
+	i int32
+}
+
+func (v *Int32) Load() (val int32) {
+	return atomic.LoadInt32(&v.i)
+}
+
+func (v *Int32) Store(val int32) {
+	atomic.StoreInt32(&v.i, val)
+}
+
+func (v *Int32) Swap(new int32) (old int32) {
+	return atomic.SwapInt32(&v.i, new)
+}
+
+func (v *Int32) CompareAndSwap(old, new int32) (swapped bool) {
+	return atomic.CompareAndSwapInt32(&v.i, old, new)
+}
+
+func (v *Int32) Add(i int32) (new int32) {
+	return atomic.AddInt32(&v.i, i)
+}
diff --git a/lang/atomic/Int64.go b/lang/atomic/Int64.go
new file mode 100644
index 0000000..a5a1b23
--- /dev/null
+++ b/lang/atomic/Int64.go
@@ -0,0 +1,29 @@
+package atomic
+
+import (
+	"sync/atomic"
+)
+
+type Int64 struct {
+	i int64
+}
+
+func (v *Int64) Load() (val int64) {
+	return atomic.LoadInt64(&v.i)
+}
+
+func (v *Int64) Store(val int64) {
+	atomic.StoreInt64(&v.i, val)
+}
+
+func (v *Int64) Swap(new int64) (old int64) {
+	return atomic.SwapInt64(&v.i, new)
+}
+
+func (v *Int64) CompareAndSwap(old, new int64) (swapped bool) {
+	return atomic.CompareAndSwapInt64(&v.i, old, new)
+}
+
+func (v *Int64) Add(i int64) (new int64) {
+	return atomic.AddInt64(&v.i, i)
+}
diff --git a/lang/atomic/Reference.go b/lang/atomic/Reference.go
new file mode 100644
index 0000000..dc9baee
--- /dev/null
+++ b/lang/atomic/Reference.go
@@ -0,0 +1,46 @@
+package atomic
+
+import (
+	"sync/atomic"
+	"unsafe"
+)
+
+type Reference[T any] struct {
+	reference *T
+}
+
+func NewReference[T any](reference *T) *Reference[T] {
+	return &Reference[T]{reference}
+}
+
+func (v *Reference[T]) Load() (val *T) {
+	return LoadPointer(&v.reference)
+}
+
+func (v *Reference[T]) Store(val *T) {
+	StorePointer(&v.reference, val)
+}
+
+func (v *Reference[T]) Swap(new *T) (old *T) {
+	return SwapPointer(&v.reference, new)
+}
+
+func (v *Reference[T]) CompareAndSwap(old, new *T) (swapped bool) {
+	return CompareAndSwapPointer(&v.reference, old, new)
+}
+
+func LoadPointer[T any](addr **T) (val *T) {
+	return (*T)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(addr))))
+}
+
+func StorePointer[T any](addr **T, val *T) {
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(addr)), unsafe.Pointer(val))
+}
+
+func SwapPointer[T any](addr **T, new *T) (old *T) {
+	return (*T)(atomic.SwapPointer((*unsafe.Pointer)(unsafe.Pointer(addr)), unsafe.Pointer(new)))
+}
+
+func CompareAndSwapPointer[T any](addr **T, old, new *T) (swapped bool) {
+	return atomic.CompareAndSwapPointer((*unsafe.Pointer)(unsafe.Pointer(addr)), unsafe.Pointer(old), unsafe.Pointer(new))
+}
diff --git a/lang/atomic/Reference_test.go b/lang/atomic/Reference_test.go
new file mode 100644
index 0000000..10fe162
--- /dev/null
+++ b/lang/atomic/Reference_test.go
@@ -0,0 +1,15 @@
+package atomic
+
+import (
+	"fmt"
+	"github.com/tursom/GoCollections/lang"
+	"testing"
+)
+
+func TestAtomic_Store(t *testing.T) {
+	a := &Reference[lang.Int]{}
+	var i lang.Int = 1
+	a.Store(&i)
+	i = 2
+	fmt.Println(a.Load())
+}
diff --git a/lang/atomic/UInt32.go b/lang/atomic/UInt32.go
new file mode 100644
index 0000000..067d8d7
--- /dev/null
+++ b/lang/atomic/UInt32.go
@@ -0,0 +1,29 @@
+package atomic
+
+import (
+	"sync/atomic"
+)
+
+type UInt32 struct {
+	i uint32
+}
+
+func (v *UInt32) Load() (val uint32) {
+	return atomic.LoadUint32(&v.i)
+}
+
+func (v *UInt32) Store(val uint32) {
+	atomic.StoreUint32(&v.i, val)
+}
+
+func (v *UInt32) Swap(new uint32) (old uint32) {
+	return atomic.SwapUint32(&v.i, new)
+}
+
+func (v *UInt32) CompareAndSwap(old, new uint32) (swapped bool) {
+	return atomic.CompareAndSwapUint32(&v.i, old, new)
+}
+
+func (v *UInt32) Add(i uint32) (new uint32) {
+	return atomic.AddUint32(&v.i, i)
+}
diff --git a/lang/atomic/UInt64.go b/lang/atomic/UInt64.go
new file mode 100644
index 0000000..cb2473e
--- /dev/null
+++ b/lang/atomic/UInt64.go
@@ -0,0 +1,29 @@
+package atomic
+
+import (
+	"sync/atomic"
+)
+
+type UInt64 struct {
+	i uint64
+}
+
+func (v *UInt64) Load() (val uint64) {
+	return atomic.LoadUint64(&v.i)
+}
+
+func (v *UInt64) Store(val uint64) {
+	atomic.StoreUint64(&v.i, val)
+}
+
+func (v *UInt64) Swap(new uint64) (old uint64) {
+	return atomic.SwapUint64(&v.i, new)
+}
+
+func (v *UInt64) CompareAndSwap(old, new uint64) (swapped bool) {
+	return atomic.CompareAndSwapUint64(&v.i, old, new)
+}
+
+func (v *UInt64) Add(i uint64) (new uint64) {
+	return atomic.AddUint64(&v.i, i)
+}