Quiz 6 -- Linked Lists

Please write your name and lab section letter at the top of the page.

1. class ListItem {
      public int number;
      public ListItem next;
   
      ListItem(int number, ListItem next) {
         this.number = number;
         this.next = next;
      }
   
      public String toString() {
         if (next == null)
            return (" " + number);
         else
            return (" " + number + next.toString());
      }
   }
   

   Using circles to show each ListItem, draw a picture showing the linked lists created by the code:

     ListItem a = new ListItem(100, null),
              b = new ListItem(200, a),
              c = new ListItem(300, b),
              d = new ListItem(400, a);
   

2.   StackOfInts stack = new StackOfInts();
     stack.push(101);
     stack.push(102);
     stack.push(103);
   
     int a = stack.pop(), b = stack.pop(), c = stack.pop();
   

   What values are stored in a, b, and c?

3.    QueueOfInts queue = new QueueOfInts();
      queue.enqueue(101),
      queue.enqueue(102),
      queue.enqueue(103);
   
     int a = queue.dequeue(), b = queue.dequeue(), c = queue.dequeue();
   

   What values are stored in a, b, and c?