Score : $350$ points

问题陈述

AtCoder Land的一家纪念品商店出售$N$个盒子。

这些盒子编号为$1$到$N$，第$i$个盒子的价格为$A_i$日元，并且包含$A_i$块糖果。

高桥想要从$N$个盒子中购买$M$个，并将每个盒子分别送给名为$1, 2, \ldots, M$的$M$个人。

在这里，他想要购买能够满足以下条件的盒子：

• 对于每个$i = 1, 2, \ldots, M$，第$i$个人将获得一个至少包含$B_i$块糖果的盒子。

请注意，不允许将多个盒子送给一个人，或者将同一个盒子送给多个人。

确定是否可能购买$M$个盒子以满足条件，如果可能，请找出高桥需要支付的最低总金额。

以上为大语言模型 kimi 翻译，仅供参考。

Problem Statement

A souvenir shop at AtCoder Land sells $N$ boxes.

The boxes are numbered $1$ to $N$, and box $i$ has a price of $A_i$ yen and contains $A_i$ pieces of candy.

Takahashi wants to buy $M$ out of the $N$ boxes and give one box each to $M$ people named $1, 2, \ldots, M$.

Here, he wants to buy boxes that can satisfy the following condition:

• For each $i = 1, 2, \ldots, M$, person $i$ is given a box containing at least $B_i$ pieces of candy.

Note that it is not allowed to give more than one box to a single person or to give the same box to multiple people.

Determine whether it is possible to buy $M$ boxes that can satisfy the condition, and if it is possible, find the minimum total amount of money Takahashi needs to pay.

Constraints

• $1 \leq M \leq N \leq 2 \times 10^5$
• $1 \leq A_i, B_i \leq 10^9$
• All input values are integers.

Input

The input is given from Standard Input in the following format:

$N$ $M$

$A_1$ $A_2$ $\ldots$ $A_N$

$B_1$ $B_2$ $\ldots$ $B_M$

Output

If it is possible to buy $M$ boxes that can satisfy the condition, print the minimum total amount of money Takahashi needs to pay. Otherwise, print $-1$.

Sample Input 1

4 2
3 4 5 4
1 4

Sample Output 1

7

Takahashi can buy boxes $1$ and $4$, and give box $1$ to person $1$ and box $4$ to person $2$ to satisfy the condition.

In this case, he needs to pay $7$ yen in total, and it is impossible to satisfy the condition by paying less than $7$ yen, so print $7$.

Sample Input 2

3 3
1 1 1
1000000000 1000000000 1000000000

Sample Output 2

-1

Sample Input 3

7 3
2 6 8 9 5 1 11
3 5 7

Sample Output 3

19