commit 9f3c498f5b97eb6c966a159f7e11f7f7f2180fa2
Author: milarin <milaring@proton.me>
Date:   Fri Jan 20 21:48:46 2023 +0100

    initial commit

diff --git a/impl_list_array.go b/impl_list_array.go
new file mode 100644
index 0000000..954e2a6
--- /dev/null
+++ b/impl_list_array.go
@@ -0,0 +1,58 @@
+package ds
+
+type ArrayList[T any] struct {
+	values []T
+}
+
+var _ List[int] = &ArrayList[int]{}
+
+func NewArrayList[T any](initCap int) *ArrayList[T] {
+	return &ArrayList[T]{make([]T, 0, initCap)}
+}
+
+func (s *ArrayList[T]) init() {
+	if s.values == nil {
+		s.values = make([]T, 0)
+	}
+}
+
+func (s *ArrayList[T]) Add(value T) {
+	s.init()
+	s.values = append(s.values, value)
+}
+
+func (s *ArrayList[T]) AddAll(values Iterable[T]) {
+	values.Each(s.Add)
+}
+
+func (s *ArrayList[T]) Get(index int) T {
+	s.init()
+	return s.values[index]
+}
+
+func (s *ArrayList[T]) RemoveAt(index int) T {
+	s.init()
+	ret := s.values[index]
+	s.values = append(s.values[:index], s.values[index+1:]...)
+	return ret
+}
+
+func (s *ArrayList[T]) Clear() {
+	s.values = make([]T, 0)
+}
+
+func (s *ArrayList[T]) Size() int {
+	s.init()
+	return len(s.values)
+}
+
+func (s *ArrayList[T]) Empty() bool {
+	return s.Size() == 0
+}
+
+func (s *ArrayList[T]) Each(f func(value T)) {
+	s.init()
+	for _, value := range s.values {
+		f(value)
+	}
+}
diff --git a/impl_list_linked.go b/impl_list_linked.go
new file mode 100644
index 0000000..c860aaa
--- /dev/null
+++ b/impl_list_linked.go
@@ -0,0 +1,112 @@
+package ds
+
+type LinkedList[T any] struct {
+	head   *linkedListNode[T]
+	tail   *linkedListNode[T]
+	length int
+}
+
+var _ List[int] = &LinkedList[int]{}
+
+func NewLinkedList[T any]() *ArrayList[T] {
+	return &ArrayList[T]{}
+}
+
+func (l *LinkedList[T]) Add(value T) {
+	if l.length == 0 {
+		l.head = &linkedListNode[T]{value: value}
+		l.tail = l.head
+		l.length++
+		return
+	}
+
+	newNode := &linkedListNode[T]{
+		value: value,
+		prev:  l.tail,
+	}
+	l.tail.next = newNode
+	l.tail = newNode
+	l.length++
+}
+
+func (l *LinkedList[T]) AddAll(values Iterable[T]) {
+	values.Each(l.Add)
+}
+
+func (l *LinkedList[T]) Get(index int) T {
+	return l.getNode(index).value
+}
+
+func (l *LinkedList[T]) RemoveAt(index int) T {
+	node := l.getNode(index)
+
+	if node.prev != nil {
+		node.prev.next = node.next
+	} else {
+		l.head = node.next
+	}
+
+	if node.next != nil {
+		node.next.prev = node.prev
+	} else {
+		l.tail = node.prev
+	}
+
+	l.length--
+	return node.value
+}
+
+func (l *LinkedList[T]) Clear() {
+	l.head = nil
+	l.tail = nil
+	l.length = 0
+}
+
+func (l *LinkedList[T]) Each(f func(value T)) {
+	node := l.head
+	for node != nil {
+		f(node.value)
+		node = node.next
+	}
+}
+
+func (l *LinkedList[T]) Size() int {
+	return l.length
+}
+
+func (l *LinkedList[T]) Empty() bool {
+	return l.Size() == 0
+}
+
+func (l *LinkedList[T]) getNode(index int) *linkedListNode[T] {
+	if index == 0 {
+		return l.head
+	}
+
+	if index == l.length-1 {
+		return l.tail
+	}
+
+	if index > l.length/2 {
+		index = l.length - index
+		node := l.tail
+		for index > 0 {
+			node = node.prev
+			index--
+		}
+		return node
+	}
+
+	node := l.head
+	for index > 0 {
+		node = node.next
+		index--
+	}
+	return node
+}
+
+type linkedListNode[T any] struct {
+	value T
+	next  *linkedListNode[T]
+	prev  *linkedListNode[T]
+}
diff --git a/impl_queue_array.go b/impl_queue_array.go
new file mode 100644
index 0000000..de1a399
--- /dev/null
+++ b/impl_queue_array.go
@@ -0,0 +1,8 @@
+package ds
+
+type ArrayQueue[T any] ListQueue[T]
+
+func NewArrayQueue[T any]() *ArrayQueue[T] {
+	stack := NewListQueue[T](new(ArrayList[T]))
+	return (*ArrayQueue[T])(stack)
+}
diff --git a/impl_queue_linked_list.go b/impl_queue_linked_list.go
new file mode 100644
index 0000000..e500260
--- /dev/null
+++ b/impl_queue_linked_list.go
@@ -0,0 +1,8 @@
+package ds
+
+type LinkedListQueue[T any] ListQueue[T]
+
+func NewLinkedListQueue[T any]() *LinkedListQueue[T] {
+	stack := NewListQueue[T](new(LinkedList[T]))
+	return (*LinkedListQueue[T])(stack)
+}
diff --git a/impl_queue_list.go b/impl_queue_list.go
new file mode 100644
index 0000000..2b181d8
--- /dev/null
+++ b/impl_queue_list.go
@@ -0,0 +1,43 @@
+package ds
+
+type ListQueue[T any] struct {
+	list List[T]
+}
+
+var _ Queue[int] = &ListQueue[int]{}
+
+func NewListQueue[T any](list List[T]) *ListQueue[T] {
+	return &ListQueue[T]{list}
+}
+
+func (s *ListQueue[T]) Enqueue(value T) {
+	s.list.Add(value)
+}
+
+func (s *ListQueue[T]) Add(value T) {
+	s.Enqueue(value)
+}
+
+func (s *ListQueue[T]) AddAll(values Iterable[T]) {
+	values.Each(s.Add)
+}
+
+func (s *ListQueue[T]) Dequeue() T {
+	return s.list.RemoveAt(0)
+}
+
+func (s *ListQueue[T]) Peek() T {
+	return s.PeekAt(0)
+}
+
+func (s *ListQueue[T]) PeekAt(index int) T {
+	return s.list.Get(index)
+}
+
+func (s *ListQueue[T]) Size() int {
+	return s.list.Size()
+}
+
+func (s *ListQueue[T]) Empty() bool {
+	return s.Size() == 0
+}
diff --git a/impl_set.go b/impl_set.go
new file mode 100644
index 0000000..34d433e
--- /dev/null
+++ b/impl_set.go
@@ -0,0 +1,61 @@
+package ds
+
+type Set[T comparable] struct {
+	values map[T]struct{}
+}
+
+var _ Coll[int] = &Set[int]{}
+
+func NewSet[T comparable]() *Set[T] {
+	return &Set[T]{}
+}
+
+func (s *Set[T]) init() {
+	if s.values == nil {
+		s.values = map[T]struct{}{}
+	}
+}
+
+func (s *Set[T]) Add(value T) {
+	s.init()
+	s.values[value] = struct{}{}
+}
+
+func (s *Set[T]) AddAll(values Iterable[T]) {
+	s.init()
+	values.Each(s.Add)
+}
+
+func (s *Set[T]) Remove(value T) {
+	s.init()
+	delete(s.values, value)
+}
+
+func (s *Set[T]) RemoveAll(values Iterable[T]) {
+	values.Each(s.Remove)
+}
+
+func (s *Set[T]) Clear() {
+	s.values = map[T]struct{}{}
+}
+
+func (s *Set[T]) Has(value T) bool {
+	s.init()
+	_, ok := s.values[value]
+	return ok
+}
+
+func (s *Set[T]) Size() int {
+	s.init()
+	return len(s.values)
+}
+
+func (s *Set[T]) Empty() bool {
+	return s.Size() == 0
+}
+
+func (s *Set[T]) Each(f func(value T)) {
+	for value := range s.values {
+		f(value)
+	}
+}
diff --git a/impl_stack_array.go b/impl_stack_array.go
new file mode 100644
index 0000000..13fbd2a
--- /dev/null
+++ b/impl_stack_array.go
@@ -0,0 +1,8 @@
+package ds
+
+type ArrayStack[T any] ListStack[T]
+
+func NewArrayStack[T any]() *ArrayStack[T] {
+	stack := NewListStack[T](new(ArrayList[T]))
+	return (*ArrayStack[T])(stack)
+}
diff --git a/impl_stack_linked_list.go b/impl_stack_linked_list.go
new file mode 100644
index 0000000..46698a9
--- /dev/null
+++ b/impl_stack_linked_list.go
@@ -0,0 +1,8 @@
+package ds
+
+type LinkedListStack[T any] ListStack[T]
+
+func NewLinkedListStack[T any]() *ArrayStack[T] {
+	stack := NewListStack[T](new(LinkedList[T]))
+	return (*ArrayStack[T])(stack)
+}
diff --git a/impl_stack_list.go b/impl_stack_list.go
new file mode 100644
index 0000000..9a59f4b
--- /dev/null
+++ b/impl_stack_list.go
@@ -0,0 +1,43 @@
+package ds
+
+type ListStack[T any] struct {
+	list List[T]
+}
+
+var _ Stack[int] = &ListStack[int]{}
+
+func NewListStack[T any](list List[T]) *ListStack[T] {
+	return &ListStack[T]{list}
+}
+
+func (s *ListStack[T]) Push(value T) {
+	s.list.Add(value)
+}
+
+func (s *ListStack[T]) Add(value T) {
+	s.Push(value)
+}
+
+func (s *ListStack[T]) AddAll(values Iterable[T]) {
+	values.Each(s.Add)
+}
+
+func (s *ListStack[T]) Pop() T {
+	return s.list.RemoveAt(s.list.Size() - 1)
+}
+
+func (s *ListStack[T]) Peek() T {
+	return s.PeekAt(s.Size() - 1)
+}
+
+func (s *ListStack[T]) PeekAt(index int) T {
+	return s.list.Get(index)
+}
+
+func (s *ListStack[T]) Size() int {
+	return s.list.Size()
+}
+
+func (s *ListStack[T]) Empty() bool {
+	return s.Size() == 0
+}
diff --git a/int_coll.go b/int_coll.go
new file mode 100644
index 0000000..9b096f7
--- /dev/null
+++ b/int_coll.go
@@ -0,0 +1,8 @@
+package ds
+
+type Coll[T any] interface {
+	Addable[T]
+	Iterable[T]
+	Sized
+	Clearable
+}
diff --git a/int_list.go b/int_list.go
new file mode 100644
index 0000000..ce3c8bc
--- /dev/null
+++ b/int_list.go
@@ -0,0 +1,7 @@
+package ds
+
+type List[T any] interface {
+	Coll[T]
+	Indexable[int, T]
+	IndexedRemovable[int, T]
+}
diff --git a/int_map.go b/int_map.go
new file mode 100644
index 0000000..0ffdd02
--- /dev/null
+++ b/int_map.go
@@ -0,0 +1 @@
+// TODO
\ No newline at end of file
diff --git a/int_queue.go b/int_queue.go
new file mode 100644
index 0000000..921e02a
--- /dev/null
+++ b/int_queue.go
@@ -0,0 +1,12 @@
+package ds
+
+type Queue[T any] interface {
+	Addable[T]
+	Sized
+
+	Enqueue(value T)
+	Dequeue() T
+
+	Peek() T
+	PeekAt(index int) T
+}
diff --git a/int_stack.go b/int_stack.go
new file mode 100644
index 0000000..86afb80
--- /dev/null
+++ b/int_stack.go
@@ -0,0 +1,12 @@
+package ds
+
+type Stack[T any] interface {
+	Addable[T]
+	Sized
+
+	Push(value T)
+	Pop() T
+
+	Peek() T
+	PeekAt(index int) T
+}
diff --git a/int_tree.go b/int_tree.go
new file mode 100644
index 0000000..0ffdd02
--- /dev/null
+++ b/int_tree.go
@@ -0,0 +1 @@
+// TODO
\ No newline at end of file
diff --git a/interfaces.go b/interfaces.go
new file mode 100644
index 0000000..d959027
--- /dev/null
+++ b/interfaces.go
@@ -0,0 +1,36 @@
+package ds
+
+type Addable[T any] interface {
+	Add(value T)
+	AddAll(values Iterable[T])
+}
+
+type Retrievable[T comparable] interface {
+	Has(value T) bool
+}
+
+type Indexable[K comparable, T any] interface {
+	Get(index K) T
+}
+
+type IndexedRemovable[K comparable, T any] interface {
+	RemoveAt(index K) T
+}
+
+type ComparingRemovable[T any] interface {
+	Remove(value T)
+	RemoveAll(values Iterable[T])
+}
+
+type Clearable interface {
+	Clear()
+}
+
+type Sized interface {
+	Size() int
+	Empty() bool
+}
+
+type Iterable[T any] interface {
+	Each(f func(value T))
+}