program main implicit none real*8, allocatable :: a(:), b(:), c(:), x(:) real*8 time integer*8 time0, time1, dtime integer i, j, n, m c n = 10000 m = 100000 c Initialization allocate(a(n), b(n), c(n), x(n)) do i=1,n a(i) = rand() b(i) = rand() c(i) = rand() end do c Start time call system_clock(time0) c Main calculation do j=1,m do i=1,n x(i) = 1d0 + a(i) * (2d0 + b(i) * (1d0 + c(i))) end do end do c Finish time call system_clock(time1, dtime) c Output time time = 1d0*(time1-time0)/dtime write(*,"(a7,f16.7)")"Time = ",time deallocate(a, b, c, x) end program