B. Balanced Tunnel

链接：https://codeforces.com/contest/1237/problem/B

Consider a tunnel on a one-way road. During a particular day, nn cars numbered from 11 to nn entered and exited the tunnel exactly once. All the cars passed through the tunnel at constant speeds.

A traffic enforcement camera is mounted at the tunnel entrance. Another traffic enforcement camera is mounted at the tunnel exit. Perfectly balanced.

Thanks to the cameras, the order in which the cars entered and exited the tunnel is known. No two cars entered or exited at the same time.

Traffic regulations prohibit overtaking inside the tunnel. If car ii overtakes any other car jj inside the tunnel, car ii must be fined. However, each car can be fined at most once.

Formally, let's say that car ii definitely overtook car jj if car ii&nb