MIJN
//breadth-first
digraph G {
n_6_6->n_6_5;
n_6_6->n_7_6;
n_6_6->n_6_7;
n_6_6->n_5_6;
n_6_5->n_7_5;
n_6_5->n_5_5;
n_7_5->n_8_5;

n_5_5->n_4_5;
n_8_5->n_8_4;
n_8_5->n_9_5;
n_4_5->n_4_4;
n_4_5->n_3_5;