// file: ll_remove_0.cc//// isip include files//#include "link_list.h"#include "link_list_constants.h"// method: remove_cc//// arguments://  Link_node* node : (input) a link node to remove from the list//// return: a logical_1 to indicate success//// this method removes the specified node from the linked list//logical_1 Link_list::remove_cc(Link_node* node_a) {  // exit ungracefully if the node is null  //  if (node_a == (Link_node*)NULL) {    return ISIP_FALSE;  }  // note the previous node of this node  //  Link_node* pnode = node_a->get_prev_cc();    // if the head pointer is to be removed reset the head pointer  //  if (head_d == node_a) {    head_d = head_d->get_next_cc();    if (head_d != (Link_node*)NULL) {      head_d->set_prev_cc(pnode);    }  }    // otherwise remove the specified node from the list  //  else {    head_d->remove_cc(node_a);  }    // adjust current pointer if necessary  //  if (curr_d == node_a) {    curr_d = pnode;  }    // return the removed node to the free links pot in the memory manager  //  manager_d->delete_cc(node_a);    // exit gracefully  //  return ISIP_TRUE;}