s1 -> s3 s3 -> s1 s1 -> s4 s4 -> s1 s1 -> s5 s5 -> s1 s2 -> s4 s4 -> s2 s2 -> s5 s5 -> s2 s2 -> s6 s6 -> s2 s7 -> s8 s8 -> s7 s3 -> s7 s7 -> s3 s4 -> s7 s7 -> s4 s5 -> s7 s7 -> s5 s6 -> s7 s7 -> s6 s8 -> s9 s9 -> s8 s8 -> s10 s10 -> s8 s8 -> s11 s11 -> s8 s8 -> s12 s12 -> s8 s6 -> s9 s9 -> s6 s8 -> s13 s13 -> s8 s5 -> s13 s13 -> s5 s5 -> s11 s11 -> s5 s14 -> s15 s15 -> s14 s8 -> s14 s14 -> s8 s15 -> s16 s16 -> s15 s15 -> s17 s17 -> s15 s15 -> s18 s18 -> s15 s15 -> s19 s19 -> s15 s9 -> s16 s16 -> s9 s9 -> s17 s17 -> s9 s9 -> s18 s18 -> s9 s11 -> s19 s19 -> s11 s20 -> s21 s21 -> s20 s15 -> s20 s20 -> s15 s21 -> s22 s22 -> s21 s21 -> s23 s23 -> s21 s21 -> s24 s24 -> s21 s21 -> s25 s25 -> s21 s21 -> s26 s26 -> s21 s21 -> s27 s27 -> s21 s16 -> s22 s22 -> s16 s17 -> s22 s22 -> s17 s17 -> s23 s23 -> s17 s18 -> s23 s23 -> s18 s17 -> s25 s25 -> s17 s16 -> s24 s24 -> s16 s18 -> s25 s25 -> s18 s28 -> s29 s29 -> s28 s30 -> s31 s31 -> s30 s32 -> s33 s33 -> s32 s34 -> s35 s35 -> s34 s36 -> s37 s37 -> s36 s38 -> s39 s39 -> s38 s40 -> s41 s41 -> s40 s42 -> s43 s43 -> s42 s44 -> s45 s45 -> s44 s46 -> s47 s47 -> s46 s22 -> s28 s28 -> s22 s24 -> s28 s28 -> s24 s23 -> s32 s32 -> s23 s24 -> s32 s32 -> s24 s24 -> s38 s38 -> s24 s23 -> s42 s42 -> s23 s25 -> s42 s42 -> s25 s25 -> s46 s46 -> s25 s25 -> s32 s32 -> s25 s23 -> s46 s46 -> s23 s23 -> s44 s44 -> s23 s25 -> s44 s44 -> s25 s23 -> s40 s40 -> s23 s25 -> s36 s36 -> s25 s21 -> s30 s30 -> s21 s21 -> s48 s48 -> s21 s21 -> s49 s49 -> s21 s21 -> s51 s51 -> s21 s21 -> s50 s50 -> s21 s24 -> s34 s34 -> s24 s45 -> s52 s52 -> s45 s31 -> s52 s52 -> s31 s49 -> s52 s52 -> s49 s50 -> s52 s52 -> s50 s51 -> s52 s52 -> s51 s48 -> s52 s52 -> s48 s37 -> s52 s52 -> s37 s41 -> s52 s52 -> s41 s35 -> s52 s52 -> s35 s29 -> s52 s52 -> s29 s47 -> s52 s52 -> s47 s43 -> s52 s52 -> s43 s39 -> s52 s52 -> s39 s33 -> s52 s52 -> s33