"The expectedMean should be the same as computeMeanSafely",
        expectedMean,
        computeMeanSafely(x, y));
    assertMean(x, y);
  }

  /**
   * Helper method that asserts the arithmetic mean of x and y is equal to the result of
   * computeMeanSafely.
   */
  private static void assertMean(int x, int y) {
    int expectedMean = computeMeanSafely(x, y);

        "The expectedMean should be the same as computeMeanSafely",
        expectedMean,
        computeMeanSafely(x, y));
    assertMean(x, y);
  }

  /**
   * Helper method that asserts the arithmetic mean of x and y is equal to the result of
   * computeMeanSafely.
   */
  private static void assertMean(long x, long y) {
    long expectedMean = computeMeanSafely(x, y);