test_div.f90

PROGRAM test_div
  IMPLICIT NONE
  INTEGER :: count1, count_rate1, count_max1
  INTEGER :: count2, count_rate2, count_max2
  INTEGER :: N
  REAL(8), allocatable :: a(:), b(:), c(:)
  read(*,*) N
  allocate(a(N), b(N), c(N))
  CALL RANDOM_NUMBER(a)
  CALL RANDOM_NUMBER(b)
  CALL SYSTEM_CLOCK(count1, count_rate1, count_max1)
  WRITE(*,*) count1, count_rate1, count_max1
  CALL div(a, b, c)
  CALL SYSTEM_CLOCK(count2, count_rate2, count_max2)
  WRITE(*,*) count2, count_rate2, count_max2
  WRITE(*,*) count2-count1
  WRITE(7,*) c(1:3)
CONTAINS
  SUBROUTINE div(a, b, c)
    REAL(8), INTENT(IN) :: a(:), b(:)
    REAL(8), INTENT(OUT) :: c(:)
    c = a / b
  END SUBROUTINE div
END PROGRAM