Wiring

Maryam is an electrical engineer. She is designing wiring on a communication tower. On the tower there are some connection points, placed at distinct heights. A wire can be used to connect any two connection points. Each connection point can be connected to an arbitrary number of wires. There are two types of connection points: red and blue.

For the purpose of this problem the tower should be viewed as a line and the connection points as blue and red points that are at non-negative integer coordinates on this line. The length of a wire is the distance between the two connection points it connects.

Your goal is to help Maryam find a wiring scheme such that:

1. Each connection point has at least one wire to a connection point of a different color.
2. The total length of the wires is minimized.

• $1 \leq n, m \leq 100\\,000$,
• $0 \leq r\[i] \leq 10^9$ (for all $0 \leq i \leq n-1$),
• $0 \leq b\[i] \leq 10^9$ (for all $0 \leq i \leq m-1$),
• Each of the arrays $r$ and $b$ is sorted in ascending order.
• All $n+m$ values in the arrays $r$ and $b$ are distinct.