/**
   * Returns a hash function implementing the Message Authentication Code (MAC) algorithm, using the
   * MD5 (128 hash bits) hash function and a {@link SecretKeySpec} created from the given byte array
   * and the MD5 algorithm.
   *
   * <p>If you are designing a new system that needs HMAC, prefer {@link #hmacSha256} or other
   * future-proof algorithms <a

      return b;
    } else if (b == 0) {
      return a; // similar logic
    }
    /*
     * Uses the binary GCD algorithm; see http://en.wikipedia.org/wiki/Binary_GCD_algorithm. This is
     * >40% faster than the Euclidean algorithm in benchmarks.
     */
    int aTwos = Integer.numberOfTrailingZeros(a);
    a >>= aTwos; // divide out all 2s
    int bTwos = Integer.numberOfTrailingZeros(b);

  }

  /**
   * Returns a {@link Collection} of all the permutations of the specified {@link Iterable}.
   *
   * <p><i>Notes:</i> This is an implementation of the algorithm for Lexicographical Permutations
   * Generation, described in Knuth's "The Art of Computer Programming", Volume 4, Chapter 7,
   * Section 7.2.1.2. The iteration order follows the lexicographical order. This means that the

      }
    };

    abstract int resultIndex(int higherIndex);
  }

  /**
   * Searches the specified naturally ordered list for the specified object using the binary search
   * algorithm.
   *
   * <p>Equivalent to {@link #binarySearch(List, Function, Object, Comparator, KeyPresentBehavior,
   * KeyAbsentBehavior)} using {@link Ordering#natural}.
   */

     * be null instead of the actual module name. This option can avoid the cost of reading module
     * descriptors when only the modules existence needs to be verified.</p>
     *
     * <p><b>Algorithm:</b>
     * If the given path is a directory, then there is a choice:
     * </p>
     * <ul>
     *   <li><b>Package hierarchy:</b> if a {@code module-info.class} file is found at the root,

  }

  /**
   * Returns a {@link Collection} of all the permutations of the specified {@link Iterable}.
   *
   * <p><i>Notes:</i> This is an implementation of the algorithm for Lexicographical Permutations
   * Generation, described in Knuth's "The Art of Computer Programming", Volume 4, Chapter 7,
   * Section 7.2.1.2. The iteration order follows the lexicographical order. This means that the

      return b;
    } else if (b == 0) {
      return a; // similar logic
    }
    /*
     * Uses the binary GCD algorithm; see http://en.wikipedia.org/wiki/Binary_GCD_algorithm. This is
     * >60% faster than the Euclidean algorithm in benchmarks.
     */
    int aTwos = Long.numberOfTrailingZeros(a);
    a >>= aTwos; // divide out all 2s
    int bTwos = Long.numberOfTrailingZeros(b);

     * and the arithmetic mean is always higher than the geometric mean.
     *
     * b) this iteration converges to floor(sqrt(x)). In fact, the number of correct digits doubles
     * with each iteration, so this algorithm takes O(log(digits)) iterations.
     *
     * We start out with a double-precision approximation, which may be higher or lower than the
     * true value. Therefore, we perform at least one Newton iteration to get a guess that's

 * subtype of {@code ValueGraph} that provides methods for adding and removing nodes and edges. If
 * you do not need to mutate a graph (e.g. if you write a method than runs a read-only algorithm on
 * the graph), you should use the non-mutating {@link ValueGraph} interface, or an {@link
 * ImmutableValueGraph}.
 *
 * <p>You can create an immutable copy of an existing {@code ValueGraph} using {@link

  }

  // Ordering<Object> singletons

  /**
   * Returns an ordering which treats all values as equal, indicating "no ordering." Passing this
   * ordering to any <i>stable</i> sort algorithm results in no change to the order of elements.
   * Note especially that {@link #sortedCopy} and {@link #immutableSortedCopy} are stable, and in
   * the returned instance these are implemented by simply copying the source list.