t18 t18 t1 t1 t2 t2 t3 t3 t4 t4 t5 t5 t6 t6 t7 t7 t9 t9 t10 t10 t12 t12 t13 t13 t14 t14 t15 t15 t16 t16 t17 t17 t19 t19 t21 t21 t20 t20 t23 t23