Four Cases

Here the method. Look at the pictures on the previous page and select the correct conditional expression for each blank.

Keep in mind short-circuit evaluation.

• headPtr.getValue()==value
• next!=null && next.getValue() == value
• headPtr==null
• next!=null && next.getValue() < value

public class OrderedLinkedList
{
  private Node headPtr = null;
 
  . . . .
  
  // Delete the first node that contains value.
  // if a node was deleted, return true
  // if the value was not found, return false
  //
  public boolean deleteValue(int value)
  {
    // CASE I: Empty list 
    if (   ) return false;
      
    // CASE II: Delete first node
    // value is in first node, unlink it, return true
    if (  )
    {
      headPtr = headPtr.getNext();
      return true;
    }

    // CASE III and CASE IV: delete middle or last node.
    // Search for a node that contains value.
    // Might be last one.
    Node current = headPtr;
    Node next = headPtr.getNext();
    
    while (   )
    {
      current = next;         // advance both
      next = next.getNext();  // pointers
    }
    
    // if value is found, give current node
    // the pointer in next node, which might be null
    if (   )
    {
      current.setNext( next.getNext() );
      return true;
    }
    
    // value not in the list: return false
    return false;
  }
  . . .
}