program main
    implicit none
    integer k
    character s*100
    character(:), allocatable :: s1
    integer i
    read(*,*) k
    read(*,*) s
    i = len_trim(s)

    if (i <= k ) then
        write(*,*) s
    else
        allocate(character(k+3) :: s1)
        s1(1:k) = s(1:k)
        s1(k+1:k+1) = "."
        s1(k+2:k+2) = "."
        s1(k+3:k+3) = "."
        write(*,*) s1
        deallocate(s1)
    end if

end program