program main
  implicit none
  integer i, N, tit
  character(100) S, T
  character(200) ans
  read(*, *) N
  read(*, *) S, T
  !read(*, *) (L(i), i = 1,N)
  tit = 1
  do i = 1,N
    ans(tit:tit) = S(i:i)
    tit = tit + 1
    ans(tit:tit) = T(i:i)
    tit = tit + 1
  end do
  write(*, *) ans(1:tit-1)
end program main
