Java, Data Structures, Arraylist, Set, Hashmap.
HashSet or TreeSet and use the entrySet() method to get a set of entries from the Map. Example: Map<String, Integer> map = new HashMap<>(); map.put("foo", 1); map.put("bar", 2); map.put("baz", 3); Set<Map.Entry<String, Integer>> set = new HashSet<>(map.entrySet()); These are the top 10 tips for