Which Of The Following Piece Of Code Has The Functionality Of #80

 public int length(Node head) { int size = 0; Node cur = head; while(cur!=null) { size++; cur = cur.getNext(); } return size; }

 public int length(Node head) { int size = 0; Node cur = head; while(cur!=null) { cur = cur.getNext(); size++; } return size; }

 public int length(Node head) { int size = 0; Node cur = head; while(cur!=null) { size++; cur = cur.getNext(); } }

 public int length(Node head) { int size = 0; Node cur = head; while(cur!=null) { size++; cur = cur.getNext().getNext(); } return size; }