Problem A

Statement
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Description:
VK news recommendation system daily selects interesting publications of one of $$$n$$$ disjoint categories for each user. Each publication belongs to exactly one category. For each category $$$i$$$ batch algorithm selects $$$a_i$$$ publications.

The latest A/B test suggests that users are reading recommended publications more actively if each category has a different number of publications within daily recommendations. The targeted algorithm can find a single interesting publication of $$$i$$$-th category within $$$t_i$$$ seconds.

What is the minimum total time necessary to add publications to the result of batch algorithm execution, so all categories have a different number of publications? You can't remove publications recommended by the batch algorithm.

Input Format:
The first line of input consists of single integer $$$n$$$ — the number of news categories ($$$1 \le n \le 200\,000$$$).

The second line of input consists of $$$n$$$ integers $$$a_i$$$ — the number of publications of $$$i$$$-th category selected by the batch algorithm ($$$1 \le a_i \le 10^9$$$).

The third line of input consists of $$$n$$$ integers $$$t_i$$$ — time it takes for targeted algorithm to find one new publication of category $$$i$$$ ($$$1 \le t_i \le 10^5)$$$.

Output Format:
Print one integer — the minimal required time for the targeted algorithm to get rid of categories with the same size.

Note:
In the first example, it is possible to find three publications of the second type, which will take 6 seconds.

In the second example, all news categories contain a different number of publications.