// If MaxLen is not 0, make sure MaxLen >= 4.
var MaxLen int

// PrimeRK is the prime base used in Rabin-Karp algorithm.
const PrimeRK = 16777619

// HashStr returns the hash and the appropriate multiplicative
// factor for use in Rabin-Karp algorithm.
func HashStr[T string | []byte](sep T) (uint32, uint32) {
	hash := uint32(0)
	for i := 0; i < len(sep); i++ {
		hash = hash*PrimeRK + uint32(sep[i])
	}

//
// If x == 0, Invert returns e = 0.
func (e *P256Element) Invert(x *P256Element) *P256Element {
	// Inversion is implemented as exponentiation with exponent p − 2.
	// The sequence of 12 multiplications and 255 squarings is derived from the
	// following addition chain generated with github.com/mmcloughlin/addchain v0.4.0.
	//
	//	_10     = 2*1
	//	_11     = 1 + _10
	//	_110    = 2*_11
	//	_111    = 1 + _110

 * @author Austin Appleby
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class Hashing {
  private Hashing() {}

  /*
   * These should be ints, but we need to use longs to force GWT to do the multiplications with
   * enough precision.
   */
  private static final long C1 = 0xcc9e2d51;
  private static final long C2 = 0x1b873593;

  /*

//
// If x == 0, Invert returns e = 0.
func (e *P521Element) Invert(x *P521Element) *P521Element {
	// Inversion is implemented as exponentiation with exponent p − 2.
	// The sequence of 13 multiplications and 520 squarings is derived from the
	// following addition chain generated with github.com/mmcloughlin/addchain v0.4.0.
	//
	//	_10       = 2*1
	//	_11       = 1 + _10
	//	_1100     = _11 << 2

// We want a bunch of different profile stacks that collide in the
// hash table maintained in runtime/cpuprof.go. This code knows the
// size of the hash table (1 << 10) and knows that the hash function
// is simply multiplicative.
void raceprofTraceback(void* parg) {
	struct cgoTracebackArg* arg = (struct cgoTracebackArg*)(parg);
	raceprofCount++;
	arg->buf[0] = raceprofCount * (1 << 10);
	arg->buf[1] = 0;
}

//
// If x == 0, Invert returns e = 0.
func (e *P224Element) Invert(x *P224Element) *P224Element {
	// Inversion is implemented as exponentiation with exponent p − 2.
	// The sequence of 11 multiplications and 223 squarings is derived from the
	// following addition chain generated with github.com/mmcloughlin/addchain v0.4.0.
	//
	//	_10     = 2*1
	//	_11     = 1 + _10
	//	_110    = 2*_11
	//	_111    = 1 + _110

//
// If x == 0, Invert returns e = 0.
func (e *P384Element) Invert(x *P384Element) *P384Element {
	// Inversion is implemented as exponentiation with exponent p − 2.
	// The sequence of 15 multiplications and 383 squarings is derived from the
	// following addition chain generated with github.com/mmcloughlin/addchain v0.4.0.
	//
	//	_10     = 2*1
	//	_11     = 1 + _10
	//	_110    = 2*_11
	//	_111    = 1 + _110

		f = (imag(n)*ratio - real(n)) / denom
	}

	if isNaN(e) && isNaN(f) {
		// Correct final result to infinities and zeros if applicable.
		// Matches C99: ISO/IEC 9899:1999 - G.5.1  Multiplicative operators.

		a, b := real(n), imag(n)
		c, d := real(m), imag(m)

		switch {
		case m == 0 && (!isNaN(a) || !isNaN(b)):
			e = copysign(inf, c) * a
			f = copysign(inf, c) * b

 * @author Austin Appleby
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class Hashing {
  private Hashing() {}

  /*
   * These should be ints, but we need to use longs to force GWT to do the multiplications with
   * enough precision.
   */
  private static final long C1 = 0xcc9e2d51;
  private static final long C2 = 0x1b873593;

  /*

}

// A right-leaning tree of byte multiplications.
func righttree(a, b, c, d uint8) uint8 {
	return a * (b * (c * (d *
		(a * (b * (c * (d *
			(a * (b * (c * (d *
				(a * (b * (c * (d *
					(a * (b * (c * (d *
						a * (b * (c * d)))))))))))))))))))))

}

// A left-leaning tree of byte multiplications.
func lefttree(a, b, c, d uint8) uint8 {