Read and model a directed flow network

The diagram represents a parcel-sorting network. It transfers parcels each hour. Each edge label gives a capacity in parcels/h; flow can follow an edge only in the arrow direction

The edge data are: e1: joins S and D1, capacity 65 parcels/h; e2: joins S and A, capacity 80 parcels/h; e3: joins D1 and A1, capacity 60 parcels/h; e4: joins D1 and H, capacity 115 parcels/h; e5: joins D1 and O, capacity 80 parcels/h; e6: joins A and A1, capacity 35 parcels/h; e7: joins A and H, capacity 80 parcels/h; e8: joins A and O, capacity 60 parcels/h; e9: joins A1 and H1, capacity 55 parcels/h; e10: joins A1 and C1, capacity 65 parcels/h; e11: joins A1 and B, capacity 80 parcels/h; e12: joins H and H1, capacity 75 parcels/h; e13: joins H and C1, capacity 105 parcels/h; e14: joins H and B, capacity 60 parcels/h; e15: joins O and H1, capacity 100 parcels/h; e16: joins O and C1, capacity 95 parcels/h; e17: joins O and B, capacity 30 parcels/h; e18: joins H1 and N, capacity 40 parcels/h; e19: joins C1 and N, capacity 30 parcels/h; e20: joins B and N, capacity 105 parcels/h

Use the node labels and arrows in the diagram to identify the requested roles and direction