### Question:
VectorSTL implements Iterable<T> { public static <K> void merge(VectorSTL<K> v1, VectorSTL<K> v2, VectorSTL<K> destination) { if (v1.empty() && v2.empty()) { destination.clear(); return; } K value = v1.empty() ? v2.get(0) : v1.get(0); if (!(value instanceof Comparable)) { throw new UnsupportedOperationException("T must be comparable"); } merge(v1, v2, destination, comparableComparator); } VectorSTL();  VectorSTL(int initialCapacity);  VectorSTL(int initialCapacity, T value);  VectorSTL(VectorSTL<T> other); @Override String toString(); void reserve(int capacity); IteratorSTL<T> begin(); IteratorSTL<T> end(); IteratorSTL<T> rBegin(); IteratorSTL<T> rEnd(); void clear(); int size(); boolean empty(); T get(int index); T front(); T back(); void setBack(T value); void push_back(T value); T pop_back(); void insert(int index, T value); void appendAll(VectorSTL<T> vector); void insertAll(IteratorSTL<T> pos, VectorSTL<T> vector); void insert(IteratorSTL<T> iterator, T value); void set(int index, T value); void set(IteratorSTL<T> iter, T value); @Override boolean equals(Object obj); T erase(int index); IteratorSTL<T> erase(IteratorSTL<T> it); void erase(IteratorSTL<T> start, IteratorSTL<T> end); void sort(); void sort(Comparator<T> comparator); VectorSTL<T> copy(); @Override Iterator<T> iterator(); IteratorSTL<T> lower_bound(T key, Comparator<T> comparator); IteratorSTL<T> lower_bound(T key); IteratorSTL<T> upper_bound(T key); IteratorSTL<T> upper_bound(T key, Comparator<T> comparator); static void merge(VectorSTL<K> v1, VectorSTL<K> v2, VectorSTL<K> destination); static void merge(VectorSTL<K> v1, VectorSTL<K> v2, VectorSTL<K> destination,
			Comparator<K> comparator); void resize(int size, T value); void insert(IteratorSTL<T> pos, T[] list); void assign(VectorSTL<T> otherVector);  }### Answer:
@Test public void testMerge() { VectorSTL<Integer> v1 = new VectorSTL<Integer>(); v1.push_back(3); v1.push_back(4); v1.push_back(4); v1.push_back(4); v1.push_back(7); v1.push_back(9); VectorSTL<Integer> v2 = new VectorSTL<Integer>(); v2.push_back(1); v2.push_back(2); v2.push_back(4); v2.push_back(6); v2.push_back(7); v2.push_back(10); VectorSTL<Integer> destination = new VectorSTL<Integer>(); VectorSTL.merge(v1, v2, destination); assertEquals(12, destination.size()); assertEquals(1, (int) destination.get(0)); assertEquals(2, (int) destination.get(1)); assertEquals(3, (int) destination.get(2)); assertEquals(4, (int) destination.get(3)); assertEquals(4, (int) destination.get(4)); assertEquals(4, (int) destination.get(5)); assertEquals(4, (int) destination.get(6)); assertEquals(6, (int) destination.get(7)); assertEquals(7, (int) destination.get(8)); assertEquals(7, (int) destination.get(9)); assertEquals(9, (int) destination.get(10)); assertEquals(10, (int) destination.get(11)); }