@Test
public void testLongIntSort() {
int N = 10000000;
long[] a = new long[N];
Random r = new Random(260379);
long achecksum = 0;
for (int i = 0; i < N; i++) {
a[i] = Math.abs(r.nextLong() % (N / 4));
achecksum += a[i];
}
long st = System.currentTimeMillis();
int[] b = Sorting.radixSortWithIndex(a);
System.out.println("Native radix sorting took: " + (System.currentTimeMillis() - st) + " ms");
long idxsum = 0;
long asum = 0;
for (int i = 0; i < N - 1; i++) {
assertTrue((a[i] < a[i + 1]) || (a[i] == a[i + 1] && b[i] <= b[i + 1]));
assertTrue(b[i] >= 0 && b[i] < a.length);
idxsum += b[i];
asum += a[i];
}
asum += a[N - 1];
idxsum += b[N - 1];
assertEquals(achecksum, asum);
assertEquals((long) N * ((long) N - 1) / 2, idxsum);
}
