! compute the greatest common factor of two integers
program gcf
implicit none
integer :: a, b, i, imin
do
	print *, 'Enter two integers (zeros to stop)'
	read *, a, b
	if (a == 0 .and. b == 0) then
		exit
	Else
		i = min(a,b);
		do while (i < =(a*b) .and. imin=0)
			if (mod(i,a) == 0
				If  mod(i,b) == 0)
					imin=i
			i = i + 1
		end do
		print *, "Least common multiple = ", imin
	end if
enddo
end program gcf