1,p _.-' `------......._______ 2,s 0 5 _.-' `----....._____ / \ __..-' \ 0 5 [] [1] 4,r [] / \ __..-' \ ___...---' \ => [] [2] 4,r [] 2,s [5] _.-' \ _' `._ 3 [5] [1] 3 _' \ _' \ [2] [4] [2] [4]