@Test
public void testComputeSharedSecretWithRfcIteration() throws Exception {

  byte[] k = new byte[32];
  k[0] = 9;
  byte[] prevK = k;
  k = X25519.computeSharedSecret(k, prevK);
  assertEquals(
      "422c8e7a6227d7bca1350b3e2bb7279f7897b87bb6854b783c60e80311ae3079", TestUtil.hexEncode(k));
  for (int i = 0; i < 999; i++) {
    byte[] tmp = k;
    k = X25519.computeSharedSecret(k, prevK);
    prevK = tmp;
  }
  assertEquals(
      "684cf59ba83309552800ef566f2f4d3c1c3887c49360e3875f2eb94d99532c51", TestUtil.hexEncode(k));
  // Omitting 1M iteration to limit the test runtime.
}