graph G {
node [shape=box, style=filled];
-S0;
-S1;
-S2;
-S3;
-S4;
-S5;
-S6;
-S7;
-S8;
-S9;
-S10;
-S11;
-S12;
-S13;
-S14;
-S15;
-S16;
-S17;
-S18;
-S19;
-S20;
-S21;
-S22;
-S23;
-S24;
+S0 [ pos="14,0" ];
+S1 [ pos="11,2" ];
+S2 [ pos="9,4" ];
+S3 [ pos="7,6" ];
+S4 [ pos="5,8" ];
+S5 [ pos="3,10" ];
+S6 [ pos="0,12" ];
+S7 [ pos="2,14" ];
+S8 [ pos="4,16" ];
+S9 [ pos="6,18" ];
+S10 [ pos="8,20" ];
+S11 [ pos="10,22" ];
+S12 [ pos="12,24" ];
+S13 [ pos="16,24" ];
+S14 [ pos="18,22" ];
+S15 [ pos="20,20" ];
+S16 [ pos="22,18" ];
+S17 [ pos="24,16" ];
+S18 [ pos="26,14" ];
+S19 [ pos="28,12" ];
+S20 [ pos="25,10" ];
+S21 [ pos="23,8" ];
+S22 [ pos="21,6" ];
+S23 [ pos="19,4" ];
+S24 [ pos="17,2" ];
+
node [shape=circle, style=filled];
H0;
H1;