Fix: Correct CLL display and insertion logic #1483
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This commit addresses two issues in the Circularly Linked List (CLL) implementation: 1. **Potential infinite loop in `display()`:** The `display()` method had a conditional check (`if (node.next != null)`) before advancing the node pointer. This check was redundant in a CLL and could lead to an infinite loop if `node.next` was `head` (e.g. in a single-element list). The condition has been removed, and `node = node.next` is now unconditional within the loop. 2. **Bug in `insert()` for single-element lists:** When inserting the first element into an empty list, the `node.next = head` assignment was missing, meaning the list wasn't actually made circular. This caused a `NullPointerException` when `display()` was called on such a list. The `insert()` method has been corrected to ensure `node.next = head` is set when the first element is added. A `main` method with test cases for the `display()` method (empty list, single-element list, multi-element list) has been added to `CLL.java` to verify the fixes and ensure correct behavior.
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This commit addresses two issues in the Circularly Linked List (CLL) implementation:
Potential infinite loop in
display(): Thedisplay()method had a conditional check (if (node.next != null)) before advancing the node pointer. This check was redundant in a CLL and could lead to an infinite loop ifnode.nextwashead(e.g. in a single-element list). The condition has been removed, andnode = node.nextis now unconditional within the loop.Bug in
insert()for single-element lists: When inserting the first element into an empty list, thenode.next = headassignment was missing, meaning the list wasn't actually made circular. This caused aNullPointerExceptionwhendisplay()was called on such a list. Theinsert()method has been corrected to ensurenode.next = headis set when the first element is added.A
mainmethod with test cases for thedisplay()method (empty list, single-element list, multi-element list) has been added toCLL.javato verify the fixes and ensure correct behavior.