let () =
  let n, s, t = Scanf.scanf "%d\n%s %s\n" @@ fun a b c -> a, b, c in
  let ans = Array.make (n*2) 'x' in
  for i = 0 to n-1 do
    ans.(2*i) <- s.[i]; ans.(2*i+1) <- t.[i];
  done;
  print_endline (Array.fold_left (fun s a -> s ^ Char.escaped a) "" ans)