procedure main()
    every writes(lfact(0 | !10)," ")
    write()
    write()
    every write(lfact(20 to 110 by 10))
    write()
    every writes(*lfact(1000 to 10000 by 1000)," ")
    write()
end

procedure lfact(n)
    r := 0
    f := 1
    every (i := !n, r +:= .f, f *:= .i)
    return r
end