if (result < 0) {
          result = UnsignedLongs.remainder(result, m);
        }
        // result < 2^63 again
        result += aLo * bHi; // aLo * bHi < 2^63, result < 2^64
        result = times2ToThe32Mod(result, m); // result < m < 2^63
        return plusMod(result, UnsignedLongs.remainder(aLo * bLo /* < 2^64 */, m), m);
      }

      @Override

    }

    // returns the minimum x such as x >= a && (x % b) == 0
    private static int ceilToMultiple(int a, int b) {
      int remainder = a % b;
      return remainder == 0 ? a : a + b - remainder;
    }

    void assertBytes(byte[] expected) {
      byte[] got = out.toByteArray();
      for (int i = 0; i < expected.length; i++) {
        assertEquals(expected[i], got[i]);

        if (b != 0) {
          UnsignedLong aUnsigned = UnsignedLong.fromLongBits(a);
          UnsignedLong bUnsigned = UnsignedLong.fromLongBits(b);
          long expected =
              aUnsigned.bigIntegerValue().remainder(bUnsigned.bigIntegerValue()).longValue();
          UnsignedLong unsignedRem = aUnsigned.mod(bUnsigned);
          assertThat(unsignedRem.longValue()).isEqualTo(expected);
        }
      }
    }
  }

        if (b != 0) {
          UnsignedLong aUnsigned = UnsignedLong.fromLongBits(a);
          UnsignedLong bUnsigned = UnsignedLong.fromLongBits(b);
          long expected =
              aUnsigned.bigIntegerValue().remainder(bUnsigned.bigIntegerValue()).longValue();
          UnsignedLong unsignedRem = aUnsigned.mod(bUnsigned);
          assertThat(unsignedRem.longValue()).isEqualTo(expected);
        }
      }
    }
  }

        if (isAndroid && p.equals(BAD_FOR_ANDROID_P) && q.equals(BAD_FOR_ANDROID_Q)) {
          // https://issuetracker.google.com/issues/37074172
          continue;
        }

        boolean dividesEvenly = p.remainder(q).equals(ZERO);

        try {
          BigInteger quotient = BigIntegerMath.divide(p, q, UNNECESSARY);
          BigInteger undone = quotient.multiply(q);
          if (!p.equals(undone)) {