Find usable IP range of any subnet. Network and broadcast excluded, except /31 and /32.
Range = network+1 through broadcast−1. /31 both addresses usable, /32 range is the single address.
192.168.1.50/24 → usable 192.168.1.1 – 192.168.1.254Total includes network + broadcast. Usable excludes them (minus 2), except /31 and /32.