subroutine bicycle_lock ( c, step ) !*****************************************************************************80 ! !! BICYCLE_LOCK finds the combination on a typical bicycle lock. ! ! Licensing: ! ! This code is distributed under the GNU LGPL license. ! ! Modified: ! ! 13 May 2012 ! ! Author: ! ! John Burkardt ! ! Parameters: ! ! Input, integer ( kind = 4 ) C, the combination, a value between 0 and 999. ! ! Output, integer ( kind = 4 ) STEP, the step on which the combination ! was found. A value of -1 means the combination was not found. ! implicit none integer ( kind = 4 ) a integer ( kind = 4 ) c integer ( kind = 4 ) step step = -1 do a = 0, 999 if ( a == c ) then step = a + 1 exit end if end do return end subroutine get_seed ( seed ) !*****************************************************************************80 ! !! GET_SEED returns a seed for the random number generator. ! ! Discussion: ! ! The seed depends on the current time, and ought to be (slightly) ! different every millisecond. Once the seed is obtained, a random ! number generator should be called a few times to further process ! the seed. ! ! Licensing: ! ! This code is distributed under the GNU LGPL license. ! ! Modified: ! ! 31 May 2007 ! ! Author: ! ! John Burkardt ! ! Parameters: ! ! Output, integer ( kind = 4 ) SEED, a pseudorandom seed value. ! implicit none integer ( kind = 4 ), parameter :: i4_huge = 2147483647 integer ( kind = 4 ) seed real ( kind = 8 ) temp character ( len = 10 ) time character ( len = 8 ) today integer ( kind = 4 ) values(8) character ( len = 5 ) zone call date_and_time ( today, time, zone, values ) temp = 0.0D+00 temp = temp + real ( values(2) - 1, kind = 8 ) / 11.0D+00 temp = temp + real ( values(3) - 1, kind = 8 ) / 30.0D+00 temp = temp + real ( values(5), kind = 8 ) / 23.0D+00 temp = temp + real ( values(6), kind = 8 ) / 59.0D+00 temp = temp + real ( values(7), kind = 8 ) / 59.0D+00 temp = temp + real ( values(8), kind = 8 ) / 999.0D+00 temp = temp / 6.0D+00 ! ! Force 0 < TEMP <= 1. ! do while ( temp <= 0.0D+00 ) temp = temp + 1.0D+00 end do do while ( 1.0D+00 < temp ) temp = temp - 1.0D+00 end do seed = int ( real ( i4_huge, kind = 8 ) * temp ) ! ! Never use a seed of 0 or maximum integer. ! if ( seed == 0 ) then seed = 1 end if if ( seed == i4_huge ) then seed = seed - 1 end if return end function i4_uniform_ab ( a, b, seed ) !*****************************************************************************80 ! !! I4_UNIFORM_AB returns a scaled pseudorandom I4 between A and B. ! ! Discussion: ! ! An I4 is an integer ( kind = 4 ) value. ! ! The pseudorandom number will be scaled to be uniformly distributed ! between A and B. ! ! Licensing: ! ! This code is distributed under the GNU LGPL license. ! ! Modified: ! ! 02 October 2012 ! ! Author: ! ! John Burkardt ! ! Reference: ! ! Paul Bratley, Bennett Fox, Linus Schrage, ! A Guide to Simulation, ! Second Edition, ! Springer, 1987, ! ISBN: 0387964673, ! LC: QA76.9.C65.B73. ! ! Bennett Fox, ! Algorithm 647: ! Implementation and Relative Efficiency of Quasirandom ! Sequence Generators, ! ACM Transactions on Mathematical Software, ! Volume 12, Number 4, December 1986, pages 362-376. ! ! Pierre L'Ecuyer, ! Random Number Generation, ! in Handbook of Simulation, ! edited by Jerry Banks, ! Wiley, 1998, ! ISBN: 0471134031, ! LC: T57.62.H37. ! ! Peter Lewis, Allen Goodman, James Miller, ! A Pseudo-Random Number Generator for the System/360, ! IBM Systems Journal, ! Volume 8, Number 2, 1969, pages 136-143. ! ! Parameters: ! ! Input, integer ( kind = 4 ) A, B, the limits of the interval. ! ! Input/output, integer ( kind = 4 ) SEED, the "seed" value, which ! should NOT be 0. On output, SEED has been updated. ! ! Output, integer ( kind = 4 ) I4_UNIFORM_AB, a number between A and B. ! implicit none integer ( kind = 4 ) a integer ( kind = 4 ) b integer ( kind = 4 ), parameter :: i4_huge = 2147483647 integer ( kind = 4 ) i4_uniform_ab integer ( kind = 4 ) k real ( kind = 4 ) r integer ( kind = 4 ) seed integer ( kind = 4 ) value if ( seed == 0 ) then write ( *, '(a)' ) ' ' write ( *, '(a)' ) 'I4_UNIFORM_AB - Fatal error!' write ( *, '(a)' ) ' Input value of SEED = 0.' stop 1 end if k = seed / 127773 seed = 16807 * ( seed - k * 127773 ) - k * 2836 if ( seed < 0 ) then seed = seed + i4_huge end if r = real ( seed, kind = 4 ) * 4.656612875E-10 ! ! Scale R to lie between A-0.5 and B+0.5. ! r = ( 1.0E+00 - r ) * ( real ( min ( a, b ), kind = 4 ) - 0.5E+00 ) & + r * ( real ( max ( a, b ), kind = 4 ) + 0.5E+00 ) ! ! Use rounding to convert R to an integer between A and B. ! value = nint ( r, kind = 4 ) value = max ( value, min ( a, b ) ) value = min ( value, max ( a, b ) ) i4_uniform_ab = value return end subroutine timestamp ( ) !*****************************************************************************80 ! !! TIMESTAMP prints the current YMDHMS date as a time stamp. ! ! Example: ! ! 31 May 2001 9:45:54.872 AM ! ! Licensing: ! ! This code is distributed under the GNU LGPL license. ! ! Modified: ! ! 06 August 2005 ! ! Author: ! ! John Burkardt ! ! Parameters: ! ! None ! implicit none character ( len = 8 ) ampm integer ( kind = 4 ) d integer ( kind = 4 ) h integer ( kind = 4 ) m integer ( kind = 4 ) mm character ( len = 9 ), parameter, dimension(12) :: month = (/ & 'January ', 'February ', 'March ', 'April ', & 'May ', 'June ', 'July ', 'August ', & 'September', 'October ', 'November ', 'December ' /) integer ( kind = 4 ) n integer ( kind = 4 ) s integer ( kind = 4 ) values(8) integer ( kind = 4 ) y call date_and_time ( values = values ) y = values(1) m = values(2) d = values(3) h = values(5) n = values(6) s = values(7) mm = values(8) if ( h < 12 ) then ampm = 'AM' else if ( h == 12 ) then if ( n == 0 .and. s == 0 ) then ampm = 'Noon' else ampm = 'PM' end if else h = h - 12 if ( h < 12 ) then ampm = 'PM' else if ( h == 12 ) then if ( n == 0 .and. s == 0 ) then ampm = 'Midnight' else ampm = 'AM' end if end if end if write ( *, '(i2,1x,a,1x,i4,2x,i2,a1,i2.2,a1,i2.2,a1,i3.3,1x,a)' ) & d, trim ( month(m) ), y, h, ':', n, ':', s, '.', mm, trim ( ampm ) return end