Remove After Node in Doubly Linked List

Node* removeAfterNode(int index,int len){
        Node* temp = head ;   
	Node* ref_Node=NULL ; 
	if(len==0){
    	cout<<"List is empty" ;
    	head = NULL ; 
	}
	else if(index > len || index<0){
 		cout << "Index is invalid" << endl ; 
 		head = NULL ; 
	}
	else{
             int i = 0 ;
	     while(i != index+1){
	    	  if(i==index){
	    	     ref_Node = temp ;
	    	     i++ ; 
	           }
		  else{
		     temp = temp -> next ;
	             i++ ;
	           } 
              }
             Node* new_ref = ref_Node -> next ;
             Node* back=new_ref->pre ; 
	     Node* forw=new_ref->next ; 
	     if(new_ref->next==NULL){
	    	  tail = ref_Node ; 
	    	  back = NULL ; 
	    	  ref_Node->next= NULL ; 
	    	  len -- ; 
		}
	      else{
	           ref_Node -> next = forw ; 
		   forw -> pre = ref_Node ; 
	           forw = NULL ;
	           back = NULL ;        
	           len-- ; 	
		 }
         }
return head ; 
}