diff --git a/source/tinystl/container/array.h b/source/tinystl/container/array.h
index 6b176ac..48c9f47 100644
--- a/source/tinystl/container/array.h
+++ b/source/tinystl/container/array.h
@@ -12,14 +12,18 @@ template <class T, std::size_t N>
 struct array {
   // Member types
   using value_type = T;
-  using size_type = std::size_t;
-  using difference_type = std::ptrdiff_t;
   using reference = value_type &;
   using const_reference = const value_type &;
+
+  using size_type = std::size_t;
+  using difference_type = std::ptrdiff_t;
+
   using pointer = value_type *;
   using const_pointer = const value_type *;
+
   using iterator = pointer;
   using const_iterator = const_pointer;
+
   using reverse_iterator = std::reverse_iterator<iterator>;
   using const_reverse_iterator = std::reverse_iterator<const_iterator>;
 
diff --git a/source/tinystl/container/deque.h b/source/tinystl/container/deque.h
index edb28ea..a49ad25 100644
--- a/source/tinystl/container/deque.h
+++ b/source/tinystl/container/deque.h
@@ -4,6 +4,7 @@
 #include <iterator>
 #include <memory>
 
+#include "tinystl/container/split_buffer.h"
 #include "tinystl/container/vector.h"
 #include "tinystl/iterator/segmented_iterator.h"
 
@@ -201,25 +202,39 @@ template <class T, class Alloc = std::allocator<T>>
 class deque {
   using alloc_traits = std::allocator_traits<Alloc>;
 
+  using pointer_allocator =
+    alloc_traits::template rebind_alloc<typename alloc_traits::pointer>;
+  using const_pointer_allcoator =
+    alloc_traits::template rebind_alloc<typename alloc_traits::pointer>;
+
+  using map = split_buffer<typename alloc_traits::pointer, pointer_allocator>;
+  using map_pointer =
+    typename std::allocator_traits<pointer_allocator>::pointer;
+  using map_const_pointer =
+    typename std::allocator_traits<const_pointer_allcoator>::const_pointer;
+  using map_const_iterator = typename map::const_iterator;
+
 public:
   using value_type = T;
+  using reference = value_type &;
+  using const_reference = const value_type &;
+
   using allocator_type = Alloc;
+
   using size_type = typename alloc_traits::size_type;
   using difference_type = typename alloc_traits::difference_type;
-  using reference = T &;
-  using const_reference = const T &;
+
   using pointer = typename alloc_traits::pointer;
   using const_pointer = typename alloc_traits::const_pointer;
 
-  using pointer_allocator = alloc_traits::template rebind_alloc<pointer>;
-  using map_alloc_traits = std::allocator_traits<pointer_allocator>;
-  using map_pointer = typename map_alloc_traits::pointer;
-
   using iterator = deque_iterator<
     value_type, pointer, reference, map_pointer, difference_type>;
-  using const_iterator = deque_iterator<value_type, const_pointer, const_reference, map_pointer, difference_type>;
-  using reverse_iterator = std::reverse_iterator<pointer>;
-  using const_reverse_iterator = std::reverse_iterator<const_pointer>;
+  using const_iterator = deque_iterator<
+    value_type, const_pointer, const_reference, map_const_pointer,
+    difference_type>;
+
+  using reverse_iterator = std::reverse_iterator<iterator>;
+  using const_reverse_iterator = std::reverse_iterator<const_iterator>;
 
   // construct/copy/destroy
   deque();
diff --git a/source/tinystl/container/split_buffer.h b/source/tinystl/container/split_buffer.h
index f80a4d2..873c61c 100644
--- a/source/tinystl/container/split_buffer.h
+++ b/source/tinystl/container/split_buffer.h
@@ -10,19 +10,25 @@
 namespace tinystl {
 template <class T, class Alloc>
 class split_buffer {
+  using alloc_rr = std::remove_reference_t<Alloc>;
+  using alloc_traits = std::allocator_traits<alloc_rr>;
+
 public:
-  using allocator_type = Alloc;
   using value_type = T;
   using reference = value_type &;
   using const_reference = const value_type &;
-  using alloc_rr = std::remove_reference_t<allocator_type>;
-  using alloc_traits = std::allocator_traits<alloc_rr>;
+
+  using allocator_type = Alloc;
+
   using size_type = typename alloc_traits::size_type;
   using difference_type = typename alloc_traits::difference_type;
+
   using pointer = typename alloc_traits::pointer;
   using const_pointer = typename alloc_traits::const_pointer;
+
   using iterator = pointer;
   using const_iterator = const_pointer;
+
   using sentinel_type = pointer;
 
   split_buffer(const split_buffer &) = delete;
diff --git a/source/tinystl/container/vector.h b/source/tinystl/container/vector.h
index 3aefcce..0346ed4 100644
--- a/source/tinystl/container/vector.h
+++ b/source/tinystl/container/vector.h
@@ -1,8 +1,9 @@
 #pragma once
 
+#include <algorithm>
 #include <concepts>
-#include <cstddef>
 #include <iterator>
+#include <limits>
 #include <memory>
 #include <stdexcept>
 
@@ -14,17 +15,22 @@ class vector {
 
 public:
   using value_type = T;
+  using reference = value_type &;
+  using const_reference = const value_type &;
+
   using allocator_type = Alloc;
-  using size_type = std::size_t;
-  using difference_type = std::ptrdiff_t;
-  using reference = T &;
-  using const_reference = const T &;
-  using pointer = T *;
-  using const_pointer = const T *;
-  using iterator = T *;
-  using const_iterator = const T *;
-  using reverse_iterator = std::reverse_iterator<pointer>;
-  using const_reverse_iterator = std::reverse_iterator<const_pointer>;
+
+  using size_type = typename alloc_traits::size_type;
+  using difference_type = typename alloc_traits::difference_type;
+
+  using pointer = typename alloc_traits::pointer;
+  using const_pointer = typename alloc_traits::const_pointer;
+
+  using iterator = pointer;
+  using const_iterator = const_pointer;
+
+  using reverse_iterator = std::reverse_iterator<iterator>;
+  using const_reverse_iterator = std::reverse_iterator<const_iterator>;
 
   // construct/copy/destroy
   vector() noexcept(noexcept(Alloc()));