diff --git a/include/HeapSort.h b/include/HeapSort.h
index 8659907..8feb474 100644
--- a/include/HeapSort.h
+++ b/include/HeapSort.h
@@ -21,23 +21,23 @@ namespace ling {
     protected:
         virtual bool isBig(const T &, const T &) const = 0;
 
-        [[nodiscard]] inline bool isLeft(int i) const {
+        [[nodiscard]] inline bool isLeft(const int i) const {
             return left(i) < list->size();
         }
 
-        [[nodiscard]] inline bool isRight(int i) const {
+        [[nodiscard]] inline bool isRight(const int i) const {
             return right(i) < list->size();
         }
 
-        [[nodiscard]] inline int parent(int i) {
+        [[nodiscard]] static inline int parent(const int i) {
             return (i - 1) / 2;
         }
 
-        [[nodiscard]] inline int left(int i) const {
+        [[nodiscard]] static inline int left(const int i) {
             return i * 2 + 1;
         }
 
-        [[nodiscard]] inline int right(int i) const {
+        [[nodiscard]] static inline int right(const int i) {
             return i * 2 + 2;
         }
 
@@ -50,7 +50,7 @@ namespace ling {
         }
 
         /// 下滤
-        void bottom(int i, int size) {
+        void bottom(int i, const int size) {
             while (true) {
                 int largest = i;
                 int l = left(i);
@@ -72,11 +72,13 @@ namespace ling {
         }
 
         void bottom(int i) {
-            int size = list->size();
+            const int size = list->size();
             bottom(i, size);
         }
 
     public:
+        virtual ~HeapSort() = default;
+
         explicit HeapSort(std::vector<T> &list) {
             this->list = &list;
             if (this->list->size() <= 1)
@@ -84,7 +86,7 @@ namespace ling {
         }
 
         void init() {
-            for (int i = parent(list->size() - 1); i >= 0; i--) {
+            for (int i = parent(list->size() - 1); i >= 0; --i) {
                 bottom(i);
             }
         }
@@ -96,7 +98,7 @@ namespace ling {
 
         void sort() {
             int n = list->size();
-            for (int i = n - 1; i > 0; i--) {
+            for (int i = n - 1; i > 0; --i) {
                 std::swap((*list)[0], (*list)[i]);
                 bottom(0, i);
             }
@@ -105,7 +107,7 @@ namespace ling {
     };
 
     template<typename T>
-    class HeapSortDefault : public HeapSort<T> {
+    class HeapSortDefault final : public HeapSort<T> {
     protected:
         bool isBig(const T &t, const T &t1) const override {
             return t > t1;