Counting all the nodes in a Linked List

Question

I\'m trying to write a simple method to count all the nodes in the linked list. I know there are 7 items in the linked list, but it is returning just 6 of them.

Her

Answer 1

You aren't counting the last node. When you get to the last element to be counted, n.next will be null, and so count is never incremented. You might instead try a loop like the following:

ListNode n = head;
for (ListNode n = head; n != null; n = n.next) {
  count++;
}

Answer 2

Well that's because you are starting your count from 0, neglecting the first node.

Instead initialize count=1;

Answer 3

I figured it out.

for (ListNode n = head; n != null; n = n.next)

n.next !=null was the error.

Answer 4

You want to loop until n == null. As it stands, you're stopping one short.

Answer 5

The end node will fail n.next != null but it is part the the LinkedList, so you should consider that. It sounds like you simply have an indexing error.

Answer 6

try this

public int count() {
    int count = 0;
    for (ListNode n = head; n != null; n = n.next) {
        count++;
    }
    return count;
}