Add destructors to the C++ codes.

codes/cpp/chapter_array_and_linkedlist/array.cpp

@@ -23,6 +23,8 @@ int* extend(int* nums, int size, int enlarge) {
     for (int i = 0; i < size; i++) {
         res[i] = nums[i];
     }
+    // 释放内存
+    delete[] nums;
     // 返回扩展后的新数组
     return res;
 }
@@ -82,10 +84,7 @@ int main() {
     
     /* 长度扩展 */
     int enlarge = 3;
-    int* res = extend(nums, size, enlarge);
-    int* temp = nums;
-    nums = res;
-    delete[] temp;
+    nums = extend(nums, size, enlarge);
     size += enlarge;
     cout << "将数组长度扩展至 8 ，得到 nums = ";
     PrintUtil::printArray(nums, size);
@@ -107,5 +106,9 @@ int main() {
     int index = find(nums, size, 3);
     cout << "在 nums 中查找元素 3 ，得到索引 = " << index << endl;
 
+    // 释放内存
+    delete[] arr;
+    delete[] nums;
+
     return 0;
 }

codes/cpp/chapter_array_and_linkedlist/linked_list.cpp

@@ -83,5 +83,8 @@ int main() {
     int index = find(n0, 2);
     cout << "链表中值为 2 的结点的索引 = " << index << endl;
 
+    // 释放内存
+    freeMemoryLinkedList(n0);
+
     return 0;
 }

codes/cpp/chapter_array_and_linkedlist/my_list.cpp

@@ -20,6 +20,11 @@ public:
         nums = new int[numsCapacity];
     }
 
+    /* 析构函数 */
+    ~MyList() {
+        delete[] nums;
+    }
+
     /* 获取列表长度（即当前元素数量）*/
     int size() {
         return numsSize;
@@ -90,14 +95,14 @@ public:
     void extendCapacity() {
         // 新建一个长度为 size * extendRatio 的数组，并将原数组拷贝到新数组
         int newCapacity = capacity() * extendRatio;
-        int* extend = new int[newCapacity];
+        int* tmp = nums;
+        nums = new int[newCapacity];
         // 将原数组中的所有元素复制到新数组
         for (int i = 0; i < size(); i++) {
-            extend[i] = nums[i];
+            nums[i] = tmp[i];
         }
-        int* temp = nums;
-        nums = extend;
-        delete[] temp;
+        // 释放内存
+        delete[] tmp;
         numsCapacity = newCapacity;
     }
 
@@ -160,5 +165,8 @@ int main() {
     PrintUtil::printVector(vec);
     cout << "容量 = " << list->capacity() << " ，长度 = " << list->size() << endl;
 
+    // 释放内存
+    delete list;
+
     return 0;
 }