Leader-based Team Distribution

We want to split $N$ players into $M$ teams and play a game. The sizes of the teams are $t_1,$ $t_2,$ $\cdots,$ $t_M$, and player $i$ has a leader score $L_i$ and a player score $P_i$. Each player must belong to exactly one team.

The leader of a team is the player on the team with the largest leader score. If several players on a team tie for the largest leader score, only one of them becomes the leader. The team's ability is defined as the player score of its leader.

Distribute the players among the teams so that the sum of the abilities of all teams is as large as possible.

The first line gives $N$ and $M$. ($1 \le M \le N \le 3 \cdot 10^5$)

The next $N$ lines each give two integers $L_i$ and $P_i$. ($1 \le L_i, P_i \le 10^5$)

The last line gives $M$ integers. The $i$-th of them is $t_i$. ($1 \le t_i \le N$, $\displaystyle \sum_{i=1}^M t_i = N$)

Print the maximum possible sum of the abilities of all teams over all valid distributions of the players.