// Cells and their vertices.
#0={0,1,2,3}
#1={4}

// Induced graph on cells.
#0:.
#1:->#0.

// Individual cells.
// cell #0:
0[0]: {1,2} --> 2
1[1]: {1,2} --> 2
2[2]: {1,3} --> 0,1,3
3[3]: {2,3} --> 2

// cell #1:
0[4]: {1,2,3}