Fig. 1

Sensor state transition of our algorithm. The transition conditions are as follows: a has the largest value of \(\frac {|N^{2}(v)|}{|N(v)|}\); b exists a black neighbor; c has a red neighbor but does not have black neighbor; d exists a yellow neighbor but does not have black or red neighbor; e has the largest value of \(\frac {|N^{2}(v)|}{|N(v)|}\) among all blue nodes, where N²(v) and N(v) only contain white nodes; f becomes connector; g exists a black neighbor; h has the maximum number of yellow neighbors among all red nodes; I has a red neighbor but does not have black neighbor; J becomes connector