### Question:
LinkedStack implements Stack<E> { @Override public void push(E e) { }  static void main(String[] args); @Override int size(); @Override boolean isEmpty(); @Override void push(E e); @Override E top(); @Override E pop();  }### Answer:
@Test void testPush() { LinkedStack<Integer> s = new LinkedStack<>(); for(int i = 0; i < 10; ++i) s.push(i); assertEquals(10, s.size()); assertEquals("[9, 8, 7, 6, 5, 4, 3, 2, 1, 0]", s.toString()); }
@Test void testToString() { LinkedStack<Integer> s = new LinkedStack<>(); for(int i = 0; i < 10; ++i) s.push(i); assertEquals("[9, 8, 7, 6, 5, 4, 3, 2, 1, 0]", s.toString()); }