刪除兩個map中key相同的元素

Map map = new HashMap();
map.put("1",1);
map.put("2",2);
Map map1 = new HashMap();
map1.put("1",3);
map1.put("3",5);
Set set = new HashSet();
set.addAll(map.keySet());
Set set1 = new HashSet();
set1.addAll(map1.keySet());
map.keySet().removeAll(set1);
map1.keySet().removeAll(set);