The calculated distance (air line) between Dighwāra and Samāstipur is approximately 49 miles respectively 78 kilometers.
By car or train, the actual journey to Samāstipur is certainly longer, as only the direct route (as the crow flies) between Dighwāra and Samāstipur has been calculated here.
Air line (approximately)
78 kilometers
42 nautical miles