public string RemoveFromBack()
{
if (IsEmpty())
{
throw new EmptyListException(name);
}
string removeItem = lastNode.Data;
if (firstNode == lastNode)
{
firstNode = lastNode = null;
}
else
{
ListNodeString current = firstNode;
while (current.Next != lastNode)
{
current = current.Next;
}
lastNode = current;
current.Next = null;
}
return(removeItem);
}
public void InsertAtBack(string insertItem)
{
if (IsEmpty())
{
firstNode = lastNode = new ListNodeString(insertItem);
}
else
{
lastNode = lastNode.Next = new ListNodeString(insertItem);
}
}
public void InsertAtFront(string insertItem)
{
if (IsEmpty())
{
firstNode = lastNode = new ListNodeString(insertItem);
}
else
{
firstNode = new ListNodeString(insertItem, firstNode);
}
}
public string RemoveFromFront()
{
if (IsEmpty())
{
throw new EmptyListException(name);
}
string removeItem = firstNode.Data;
if (firstNode == lastNode)
{
firstNode = lastNode = null;
}
else
{
firstNode = firstNode.Next;
}
return(removeItem);
}
public void Display()
{
if (IsEmpty())
{
Console.WriteLine($"Empty {name}");
}
else
{
Console.Write($"The {name} is: ");
ListNodeString current = firstNode;
while (current != null)
{
Console.Write($"{current.Data} ");
current = current.Next;
}
Console.WriteLine("\n");
}
}
public ListString(string listName)
{
name = listName;
firstNode = lastNode = null;
}