//
// ********************************************************************
// * License and Disclaimer                                           *
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//
//
//
#ifndef G4QUICKRAND_HH
#define G4QUICKRAND_HH

#include "G4Types.hh"
#include <cstdint>

inline G4double G4QuickRand(uint32_t seed = 0)
{
  static const G4double f = 1. / 4294967296.; // 2^-32

  // Algorithm "xor" from p.4 of G.Marsaglia, "Xorshift RNGs"
  static G4ThreadLocal uint32_t y = 2463534242;
  uint32_t x = uint32_t(seed == 0) * y + seed;
  x ^= x << 13;
  x ^= x >> 17;
  x ^= x << 5;
  y = x;
  return x * f;
}

#endif  // G4QUICKRAND_HH
