I keep getting an unhandled exception
"Object reference not set to an instance of an object"
for the following code, specifically on the line temp.next = node. Can anyone help me figure out why?
The code below is a class for birds where the user inputs a name and the addBird method is suppose to add the name to the end of the linked list.
class BirdsSurve {
private Node first;
public class Node
{
public string Name { get; set; }
public int count { get; set; }
public Node next;
public Node()
{
this.count = 1;
}
public void setNext(Node Next)
{
next = Next;
}
public int addCount()
{
count++;
return count;
}
}
public BirdsSurvey()
{
this.first = null;
}
public void addBird(string bird)
{
Node node = new Node();
node.Name = bird;
if (first == null)
{ first = node; }
else
{
Node temp = first;
while (temp != null)
{
if (temp.Name == bird)
{ temp.addCount(); }
if (temp.next == null)
{
temp = temp.next;
temp.next = node; }
// temp = temp.next;
}
}
}
