digraph G {
   node_0 [label="0: '0'"]
   node_2 [label="2: -"]
   node_6 [label="6: '2'"]
   node_10 [label="10: -"]
   node_18 [label="18: '6'"]
   node_10 -> node_18 [label="r"]
   node_6 -> node_10 [label="r"]
   node_2 -> node_6 [label="l"]
   node_4 [label="4: -"]
   node_12 [label="12: '4'"]
   node_4 -> node_12 [label="l"]
   node_8 [label="8: -"]
   node_24 [label="24: '8'"]
   node_8 -> node_24 [label="l"]
   node_4 -> node_8 [label="r"]
   node_2 -> node_4 [label="r"]
   node_0 -> node_2 [label="l"]
   node_1 [label="1: -"]
   node_5 [label="5: -"]
   node_13 [label="13: -"]
   node_21 [label="21: '7'"]
   node_13 -> node_21 [label="r"]
   node_5 -> node_13 [label="l"]
   node_9 [label="9: '3'"]
   node_5 -> node_9 [label="r"]
   node_1 -> node_5 [label="l"]
   node_3 [label="3: '1'"]
   node_11 [label="11: -"]
   node_27 [label="27: '9'"]
   node_11 -> node_27 [label="l"]
   node_3 -> node_11 [label="l"]
   node_7 [label="7: -"]
   node_15 [label="15: '5'"]
   node_7 -> node_15 [label="r"]
   node_3 -> node_7 [label="r"]
   node_1 -> node_3 [label="r"]
   node_0 -> node_1 [label="r"]
}