(h1) 1
(h2) 1-1
(h2) 1-2
(h3) 1-2-1
(h1) 2
(h2) 2-1
(h2) 2-2
(h3) 2-2-1
(h1) 1
(h2) 1-1
(h2) 1-2
(h3) 1-2-1
(h1) 2
(h2) 2-1
(h2) 2-2
(h3) 2-2-1
(h1) 1
(h2) 1-1
(h2) 1-2
(h3) 1-2-1
(h1) 2
(h2) 2-1
(h2) 2-2
(h3) 2-2-1