assertEquals(m3, k);
assertFalse(i.hasNext());
Iterator j = sm.keySet().iterator();
j.next();
j.remove();
assertFalse(map.containsKey(m2));
assertEquals(4, map.size());
assertEquals(1, sm.size());
assertEquals(m3, sm.firstKey());
assertEquals(m3, sm.lastKey());
assertEquals("C", sm.remove(m3));