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module fortran_primes_01_module
use iso_fortran_env
implicit none
integer, parameter :: IP = int32 ! Integer kind parameter for 32-bit integers
integer, parameter :: WP = int64 ! Integer kind parameter for 64-bit integers
end module fortran_primes_01_module
elemental function witnesses_for_64(n) result(i)
use fortran_primes_01_module
implicit none
integer(WP), intent(in) :: n ! Input integer with kind parameter WP
integer(WP) :: i ! Output integer with kind parameter WP
! Compute the number of Miller-Rabin witnesses for n using bitwise XOR, left shift, and multiplication
i = ieor(shifta(n, 32_WP), n) * int(z'45d9f3b3335b369', WP)
end function witnesses_for_64
program fortran_primes_01
use fortran_primes_01_module
implicit none
integer(WP) :: n, i
interface
function witnesses_for_64(n) result(i)
use fortran_primes_01_module
implicit none
integer(WP), intent(in) :: n
integer(WP) :: i
end function witnesses_for_64
end interface
n = 2_WP ! Set n to 2 (with kind parameter WP)
i = witnesses_for_64(n)
print *, i
if (i /= 629165251193693906_WP) error stop
end program
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