/**
* Returns a copy of a portion of an array.
*
* @param array an array.
* @param offset the first element to copy.
* @param length the number of elements to copy.
* @return a new array containing <code>length</code> elements of <code>array</code> starting at
* <code>offset</code>.
*/
public static long[] copy(final long[] array, final int offset, final int length) {
ensureOffsetLength(array, offset, length);
final long[] a = length == 0 ? EMPTY_ARRAY : new long[length];
System.arraycopy(array, offset, a, 0, length);
return a;
}
/**
* Creates a new tree set and fills it with the elements of a given array using a given {@link
* Comparator}.
*
* @param a an array whose elements will be used to fill the set.
* @param offset the first element to use.
* @param length the number of elements to use.
* @param c a {@link Comparator} (even better, a type-specific comparator).
*/
public LongAVLTreeSet(
final long[] a, final int offset, final int length, final Comparator<? super Long> c) {
this(c);
LongArrays.ensureOffsetLength(a, offset, length);
for (int i = 0; i < length; i++) add(a[offset + i]);
}