### Question:
BinaryTrie implements Serializable { public Map<Character, BitSequence> buildLookupTable() { buildLookupTable(ref, bt, ""); return ref; } BinaryTrie(Map<Character, Integer> frequencyTable); Match longestPrefixMatch(BitSequence querySequence); Map<Character, BitSequence> buildLookupTable();  }### Answer:
@Test public void testYourLookupTable() { System.out.println("Testing that your code outputs the right lookup table."); Map<Character, Integer> frequencyTable = new HashMap<Character, Integer>(); frequencyTable.put('a', 1); frequencyTable.put('b', 2); frequencyTable.put('c', 4); frequencyTable.put('d', 5); frequencyTable.put('e', 6); BinaryTrie trie = new BinaryTrie(frequencyTable); Map<Character, BitSequence> yourTable = trie.buildLookupTable(); HashMap<Character, BitSequence> expected = new HashMap<Character, BitSequence>(); expected.put('a', new BitSequence("000")); expected.put('b', new BitSequence("001")); expected.put('c', new BitSequence("01")); expected.put('d', new BitSequence("10")); expected.put('e', new BitSequence("11")); assertEquals(expected, yourTable); }