# include <cstdlib>
# include <iostream>
# include <iomanip>
# include <cmath>
# include <ctime>

using namespace std;

# include "asa183.hpp"

//*****************************************************************************80

float r4_random ( int *s1, int *s2, int *s3 )

//*****************************************************************************80
//
//  Purpose:
//
//    R4_RANDOM returns a pseudorandom number between 0 and 1.
//
//  Discussion:
//
//    This function returns a pseudo-random number rectangularly distributed
//    between 0 and 1.   The cycle length is 6.95E+12.  (See page 123
//    of Applied Statistics (1984) volume 33), not as claimed in the
//    original article.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license. 
//
//  Modified:
//
//    08 July 2008
//
//  Author:
//
//    Original FORTRAN77 version by Brian Wichman, David Hill.
//    C++ version by John Burkardt.
//
//  Reference:
//
//    Brian Wichman, David Hill,
//    Algorithm AS 183: An Efficient and Portable Pseudo-Random
//    Number Generator,
//    Applied Statistics,
//    Volume 31, Number 2, 1982, pages 188-190.
//
//  Parameters:
//
//    Input/output, int *S1, *S2, *S3, three values used as the
//    seed for the sequence.  These values should be positive
//    integers between 1 and 30,000.
//
//    Output, float R4_RANDOM, the next value in the sequence.
//
{
  float value;

  *s1 = ( ( 171 * *s1 ) % 30269 );
  *s2 = ( ( 172 * *s2 ) % 30307 );
  *s3 = ( ( 170 * *s3 ) % 30323 );
 
  value = fmod ( ( float ) ( *s1 ) / 30269.0 
               + ( float ) ( *s2 ) / 30307.0 
               + ( float ) ( *s3 ) / 30323.0, 1.0 );

  return value;
}
//*****************************************************************************80

float r4_uni ( int *s1, int *s2 )

//*****************************************************************************80
//
//  Purpose:
//
//    R4_UNI returns a pseudorandom number between 0 and 1.
//
//  Discussion:
//
//    This function generates uniformly distributed pseudorandom numbers
//    between 0 and 1, using the 32-bit generator from figure 3 of
//    the article by L'Ecuyer.
//
//    The cycle length is claimed to be 2.30584E+18.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license. 
//
//  Modified:
//
//    08 July 2008
//
//  Author:
//
//    Original PASCAL version by Pierre L'Ecuyer.
//    C++ version by John Burkardt.
//
//  Reference:
//
//    Pierre LEcuyer,
//    Efficient and Portable Combined Random Number Generators,
//    Communications of the ACM,
//    Volume 31, Number 6, June 1988, pages 742-751.
//
//  Parameters:
//
//    Input/output, int *S1, *S2, two values used as the
//    seed for the sequence.  On first call, the user should initialize
//    S1 to a value between 1 and 2147483562;  S2 should be initialized
//    to a value between 1 and 2147483398.
//
//    Output, float R4_UNI, the next value in the sequence.
//
{
  int k;
  float value;
  int z;

  k = *s1 / 53668;
  *s1 = 40014 * ( *s1 - k * 53668 ) - k * 12211;
  if ( *s1 < 0 )
  {
    *s1 = *s1 + 2147483563;
  }

  k = *s2 / 52774;
  *s2 = 40692 * ( *s2 - k * 52774 ) - k * 3791;
  if ( *s2 < 0 )
  {
    *s2 = *s2 + 2147483399;
  }

  z = *s1 - *s2;
  if ( z < 1 )
  {
    z = z + 2147483562;
  }

  value = ( float ) ( z ) / 2147483563.0;

  return value;
}
//*****************************************************************************80

double r8_random ( int *s1, int *s2, int *s3 )

//*****************************************************************************80
//
//  Purpose:
//
//    R8_RANDOM returns a pseudorandom number between 0 and 1.
//
//  Discussion:
//
//    This function returns a pseudo-random number rectangularly distributed
//    between 0 and 1.   The cycle length is 6.95E+12.  (See page 123
//    of Applied Statistics (1984) volume 33), not as claimed in the
//    original article.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license. 
//
//  Modified:
//
//    08 July 2008
//
//  Author:
//
//    Original FORTRAN77 version by Brian Wichman, David Hill.
//    C++ version by John Burkardt.
//
//  Reference:
//
//    Brian Wichman, David Hill,
//    Algorithm AS 183: An Efficient and Portable Pseudo-Random
//    Number Generator,
//    Applied Statistics,
//    Volume 31, Number 2, 1982, pages 188-190.
//
//  Parameters:
//
//    Input/output, int *S1, *S2, *S3, three values used as the
//    seed for the sequence.  These values should be positive
//    integers between 1 and 30,000.
//
//    Output, double R8_RANDOM, the next value in the sequence.
//
{
  double value;

  *s1 = ( ( 171 * *s1 ) % 30269 );
  *s2 = ( ( 172 * *s2 ) % 30307 );
  *s3 = ( ( 170 * *s3 ) % 30323 );
 
  value = fmod ( ( double ) ( *s1 ) / 30269.0 
               + ( double ) ( *s2 ) / 30307.0
               + ( double ) ( *s3 ) / 30323.0, 1.0 );

  return value;
}
//*****************************************************************************80

double r8_uni ( int *s1, int *s2 )

//*****************************************************************************80
//
//  Purpose:
//
//    R8_UNI returns a pseudorandom number between 0 and 1.
//
//  Discussion:
//
//    This function generates uniformly distributed pseudorandom numbers
//    between 0 and 1, using the 32-bit generator from figure 3 of
//    the article by L'Ecuyer.
//
//    The cycle length is claimed to be 2.30584E+18.
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license. 
//
//  Modified:
//
//    08 July 2008
//
//  Author:
//
//    Original PASCAL version by Pierre L'Ecuyer.
//    C++ version by John Burkardt.
//
//  Reference:
//
//    Pierre LEcuyer,
//    Efficient and Portable Combined Random Number Generators,
//    Communications of the ACM,
//    Volume 31, Number 6, June 1988, pages 742-751.
//
//  Parameters:
//
//    Input/output, int S1, S2, two values used as the
//    seed for the sequence.  On first call, the user should initialize
//    S1 to a value between 1 and 2147483562;  S2 should be initialized
//    to a value between 1 and 2147483398.
//
//    Output, double R8_UNI, the next value in the sequence.
//
{
  int k;
  double value;
  int z;

  k = *s1 / 53668;
  *s1 = 40014 * ( *s1 - k * 53668 ) - k * 12211;
  if ( *s1 < 0 )
  {
    *s1 = *s1 + 2147483563;
  }

  k = *s2 / 52774;
  *s2 = 40692 * ( *s2 - k * 52774 ) - k * 3791;
  if ( *s2 < 0 )
  {
    *s2 = *s2 + 2147483399;
  }

  z = *s1 - *s2;
  if ( z < 1 )
  {
    z = z + 2147483562;
  }

  value = ( double ) ( z ) / 2147483563.0;

  return value;
}
//****************************************************************************80

void timestamp ( )

//****************************************************************************80
//
//  Purpose:
//
//    TIMESTAMP prints the current YMDHMS date as a time stamp.
//
//  Example:
//
//    31 May 2001 09:45:54 AM
//
//  Licensing:
//
//    This code is distributed under the GNU LGPL license. 
//
//  Modified:
//
//    24 September 2003
//
//  Author:
//
//    John Burkardt
//
//  Parameters:
//
//    None
//
{
# define TIME_SIZE 40

  static char time_buffer[TIME_SIZE];
  const struct tm *tm;
  size_t len;
  time_t now;

  now = time ( NULL );
  tm = localtime ( &now );

  len = strftime ( time_buffer, TIME_SIZE, "%d %B %Y %I:%M:%S %p", tm );

  cout << time_buffer << "\n";

  return;
# undef TIME_SIZE
}