wrapped all the functions inside a class

data_structure/doubly_linked_list.cpp

@@ -9,15 +9,15 @@ struct node {
 }*start;
 
 class double_linked_list {
-   public:
-     double_linked_list() {
-       start = NULL;
-     }
-     void insert(int x);
-     void remove(int x);
-     void search(int x);
-     void show();
-     void reverseShow();
+ public:
+  double_linked_list() {
+    start = NULL;
+  }
+  void insert(int x);
+  void remove(int x);
+  void search(int x);
+  void show();
+  void reverseShow();
 };
 
 void double_linked_list::insert(int x) {