Gausstotientit.f03

! Laskee 10 miljoonaa totienttia
! Perustuu Gaussin jakajien summaan
!Juhani Kaukoranta 4.4.2021
! Fortran 95,2003
integer phi(10000000)
integer  :: n = 10000000
integer i,j
real:: start,finish
call cpu_time(start)
phi(1)=1
phi(2)=1
do i = 2,n
    phi(i) = i -1
end  do

do i = 2,n
    do j = 2*i,n,i
        phi(j) = phi(j)-phi(i)
    end do
end do

call cpu_time(finish)
write(*,*) 'Time = ',finish-start

write(*,*)'Euler totienttitaulukko OK, tulostetaan 10 viimeistä'

do i = n-10,n
    write(*,*) i,phi(i)
end do
end