Sauna Cred

Max is an avid sauna visitor. Today he's chilling in the sauna with $n$ friends. Max knows that each friend is going to visit the steam room exactly once, and the $i$-th friend is going to enter the steam room at time $l_i$, and leave at time $r_i$ (time is measured in seconds since the start of the visit). Max also wants to make a single visit to the steam room, but he can still choose his enteri