N s t

N s tN s tN s tN s t
N s tN s tN s tN s tN s tN s tN s tN s t
N s tN s tN s tN s tN s tN s tN s tN s tN s tN s tN s tN s t
N s tN s tN s tN s tN s tN s tN s tN s tN s tN s tN s tN s tN s tN s tN s tN s t
N s tN s tN s tN s tN s tN s t