public void nth_element_test()
{
int[] random =
{
1823928530,
438567658,
419543343,
1143354873,
1106789249,
2061232594,
1361344170,
1844371025,
1583434746,
820082791,
815141475
};
var a = (int[])random.Clone();
VPTreeWrapper.nth_element(a, 5);
var keys = (int[])random.Clone();
Sort.NthElement(keys, 5);
Assert.AreEqual(keys[5], a[5]);
Assert.IsTrue(a.IsEqual(keys));
}