species_0 + species_1 -> species_2
species_2 -> species_0 + species_1
species_1 + species_3 -> species_5
species_5 -> species_1 + species_3
species_1 + species_4 -> species_9
species_9 -> species_1 + species_4
species_5 -> species_6 + species_7
species_6 + species_7 -> species_5
species_6 -> species_1 + species_8
species_1 + species_8 -> species_6
species_3 + species_9 -> species_10
species_10 -> species_3 + species_9
species_4 + species_5 -> species_10
species_10 -> species_4 + species_5
species_0 + species_5 -> species_11
species_11 -> species_0 + species_5
species_0 + species_6 -> species_12
species_12 -> species_0 + species_6
species_4 + species_6 -> species_13
species_13 -> species_4 + species_6
species_10 -> species_13 + species_7
species_13 + species_7 -> species_10
species_13 -> species_8 + species_9
species_8 + species_9 -> species_13
species_2 + species_3 -> species_11
species_11 -> species_2 + species_3
species_11 -> species_12 + species_7
species_12 + species_7 -> species_11
species_12 -> species_2 + species_8
species_2 + species_8 -> species_12
species_0 + species_9 -> species_14
species_14 -> species_0 + species_9
species_2 + species_4 -> species_14
species_14 -> species_2 + species_4
species_14 + species_3 -> species_15
species_15 -> species_14 + species_3
species_11 + species_4 -> species_15
species_15 -> species_11 + species_4
species_0 + species_10 -> species_15
species_15 -> species_0 + species_10
species_15 -> species_16 + species_7
species_16 + species_7 -> species_15
species_0 + species_13 -> species_16
species_16 -> species_0 + species_13
species_12 + species_4 -> species_16
species_16 -> species_12 + species_4
species_16 -> species_14 + species_8
species_14 + species_8 -> species_16