In a doubly linked list, write a program to switch two adjacent nodes pointed by p and q. (adjacent means p- RNext==q, q->LNext==p and we assume that these two nodes are in the middle of the doubly linked list). The class definition is as follows: class DoublyLinkedList { private: int data; ListNode* LNext; //a pointer which points to the left neighbor ListNode* RNext; //a pointer which points to the right neighbor public: Swap(ListNode*, ListNode*); } DoublyLinkedList::Swap(ListNode* p, ListNode*