void printList(List& source, bool direction) {
// if (source.size() > 0) {
if (direction) {
ListItr iter = source.first();
for (int n=0; n<source.size(); n++) {
cout << iter.retrieve() << endl;
iter.moveForward();
}
}
else {
ListItr iter = source.last();
for (int n=0; n<source.size(); n++) {
cout << iter.retrieve() << endl;
iter.moveBackward();
}
}
// }
//else {
//cout << "The list is empty" << endl;
//}
}
void List::insertAfter( int x, ListItr position ) {
position.moveForward();
insertBefore(x, position);
}
int main ()
/*
** This main driver program interactively exercises a
** list package.
** It assumes a linked list implementation, and its real
** purpose is to exercise the underlying list manipulation
** procedures.
** It uses a menu to accept commands from the terminal,
** then performs the indicated command.
*/
{
int command;
string response;
List *list = NULL;
ListItr *itr = NULL;
// Initialize this run
cout << "--------------------------------------------------\n";
cout << "\tThis test harness operates with one List\n"
<< "\tobject and one ListItr object.\n\n"
<< "\tUse the menu options to manipulate these\n"
<< "\tobjects.\n";
while (1) {
command = menu(option, n_choice);
switch (command) {
case 1: // Quit
cout << "\tDo you really want to quit? (y/n) > ";
cin >> response;
if (response[0] == 'y' || response[0] == 'Y') { // Normal Exit
return 0;
}
break;
case 2: // New list
if (list != NULL) delete list;
list = new List;
cout << "\tYou have created an empty list\n";
cout << "\tDo you want to initialize it with elements? (y/n) > ";
cin >> response;
if (response[0] != 'y' && response[0] != 'Y')
break;
// accept elements
cout << "\t\tEnter elements one by one as integers.\n";
cout << "\t\tAny non-numeric character, e.g. #, ";
cout << "will terminate input\n";
cout << "\tEnter first element: ";
cin >> response;
while (isdigit(response[0])) {
int element = atoi(response.c_str());
list->insertAtTail(element);
cout << "\tEnter next element: ";
cin >> response;
}
cout << endl << "The elements in forward order: " << endl;
printList(*list, true);
break;
case 3: // show elements
if (list == NULL) {
cout << endl << "\tCreate a List first." << endl;
break;
}
cout << "\tPrint the list forwards or backwards? (f/b) > ";
cin >> response;
if (response[0] == 'b' || response[0] == 'B') {
cout << endl << "The elements in reverse order:" << endl;
printList(*list, false);
} else {
cout << endl << "The elements in forward order:" << endl;
printList(*list, true);
}
break;
case 4: // test first()
if (list == NULL) {
cout << endl << "\tCreate a List first." << endl;
break;
}
cout << "\tSetting the ListItr to the first element..." << endl;
itr = new ListItr((list->first()));
break;
case 5: // test find()
if (list == NULL) {
cout << endl << "\tCreate a List first." << endl;
break;
}
cout << "\tEnter element to find: ";
cin >> response;
if (isdigit(response[0])) {
int element = atoi(response.c_str());
itr = new ListItr((list->find(element)));
cout << "\tSetting the ListItr to find("
<< element << ")..." << endl;
} else {
cout << "\tPlease enter an integer." << endl;
}
break;
case 6: // test last()
if (list == NULL) {
cout << endl << "\tCreate a List first." << endl;
}
cout << "\tSetting the ListItr to the last element..." << endl;
itr = new ListItr((list->last()));
break;
case 7: // test moveForwards()
if (itr == NULL) {
cout << endl << "\tCreate a ListItr first." << endl;
break;
}
cout << "\tMoving the ListItr forwards..." << endl;
itr->moveForward();
break;
case 8: // test move_backwards()
if (itr == NULL) {
cout << endl << "\tCreate a ListItr first." << endl;
break;
}
cout << "\tMoving the ListItr backwards..." << endl;
itr->moveBackward();
break;
case 9: // test retrieve()
if (itr == NULL) {
cout << endl << "\tCreate a ListItr first." << endl;
break;
}
if (itr->isPastBeginning())
cout << "\tThe ListItr is past the beginning." << endl;
else if (itr->isPastEnd())
cout << "\tThe ListItr is past the end." << endl;
else
cout << "\tElement retrieved: " << itr->retrieve() << endl;
break;
case 10: // Insert element before
if (list == NULL || itr == NULL) {
cout << endl << "\tCreate a List and ListItr first." << endl;
break;
}
cout << "\tEnter element to insert: ";
cin >> response;
if (isdigit(response[0])) {
int element = atoi(response.c_str());
list->insertBefore(element, *itr);
cout << "\tInserting " << element
<< " before the current ListItr" <<endl;
} else {
cout << "\tPlease enter an integer." << endl;
break;
}
cout << endl << "The elements in forward order: " << endl;
printList(*list, true);
break;
case 11: // Insert element after
if (list == NULL || itr == NULL) {
cout << endl << "\tCreate a List and ListItr first." << endl;
break;
}
cout << "\tEnter element to insert: ";
cin >> response;
if (isdigit(response[0])) {
int element = atoi(response.c_str());
list->insertAfter(element, *itr);
cout << "\tInserting " << element
<< " after the current ListItr" <<endl;
} else {
cout << "\tPlease enter an integer." << endl;
break;
}
cout << endl << "The elements in forward order: " << endl;
printList(*list, true);
break;
case 12: // Insert element at tail
if (list == NULL) {
cout << endl << "\tCreate a List first." << endl;
break;
}
cout << "\tEnter element to insert: ";
cin >> response;
if (isdigit(response[0])) {
int element = atoi(response.c_str());
list->insertAtTail(element);
cout << "\tInserting " << element
<< " at the tail of the list" <<endl;
} else {
cout << "\tPlease enter an integer." << endl;
break;
}
cout << endl << "The elements in forward order: " << endl;
printList(*list, true);
break;
case 13: // Remove element
if (list == NULL) {
cout << endl << "\tCreate a List first." << endl;
break;
}
cout << "\tEnter element to remove: ";
cin >> response;
if (isdigit(response[0])) {
int element = atoi(response.c_str());
list->remove(element);
cout << "\tRemoving " << element
<< " from list" <<endl;
} else {
cout << "\tPlease enter an integer." << endl;
break;
}
cout << endl << "The elements in forward order: " << endl;
printList(*list, true);
break;
case 14: // test size()
if (list == NULL) {
cout << endl << "\tCreate a List first." << endl;
break;
}
cout << "\tSize of list: " << list->size() << endl;
break;
case 15: { // test copy constructor
List* old_list=list;
list=new List(*old_list);
old_list->makeEmpty();
cout << "The new list is (forward ): " ;
printList(*list, true);
cout << "The new list is (backward): " ;
printList(*list, false);
cout << "The old list was made empty (forward ): ";
printList(*old_list, true);
cout << "The old list was made empty (backward): ";
printList(*old_list, false);
cout << "The old list should be destroyed now." << endl;
delete old_list;
break;
}
case 16: { // test equals operator
List* old_list=list;
list=new List();
*list=*old_list;
old_list->makeEmpty();
cout << "The new list is (forward ): " ;
printList(*list,true);
cout << "The new list is (backward): " ;
printList(*list,false);
cout << "The old list was made empty (forward ): " ;
printList(*old_list,true);
cout << "The old list was made empty (backward): " ;
printList(*old_list,false);
cout << "The old list should be destroyed now." << endl;
delete old_list;
break;
}
case 17: // test makeEmpty()
if (list == NULL) {
cout << endl << "\tCreate a List first." << endl;
break;
}
cout << "The list is (forward ): " ;
printList(*list,true);
cout << "The list is (backward): " ;
printList(*list,false);
list->makeEmpty();
cout << "The list was made empty (forward ): " ;
printList(*list,true);
cout << "The list was made empty (backward): " ;
printList(*list,false);
} // end of switch (command)
} // end of while (1)
} // end of main()