Problem10823--ABC150 - C - Count Order

10823: ABC150 - C - Count Order

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

We have two permutations $P$ and $Q$ of size $N$ (that is, $P$ and $Q$ are both rearrangements of $(1,~2,~...,~N)$).

There are $N!$ possible permutations of size $N$. Among them, let $P$ and $Q$ be the $a$-th and $b$-th lexicographically smallest permutations, respectively. Find $|a - b|$.


Notes

For two sequences $X$ and $Y$, $X$ is said to be lexicographically smaller than $Y$ if and only if there exists an integer $k$ such that $X_i = Y_i~(1 \leq i < k)$ and $X_k < Y_k$.

Input

Input is given from Standard Input in the following format:

```
$N$
$P_1$ $P_2$ $...$ $P_N$
$Q_1$ $Q_2$ $...$ $Q_N$
```

Output

Print $|a - b|$.

Constraints

-   $2 \leq N \leq 8$
-   $P$ and $Q$ are permutations of size $N$.

Sample 1 Input

3
1 3 2
3 1 2

Sample 1 Output

3
There are $6$ permutations of size $3$: $(1,~2,~3)$, $(1,~3,~2)$, $(2,~1,~3)$, $(2,~3,~1)$, $(3,~1,~2)$, and $(3,~2,~1)$. Among them, $(1,~3,~2)$ and $(3,~1,~2)$ come $2$-nd and $5$-th in lexicographical order, so the answer is $|2 - 5| = 3$.

Sample 2 Input

8
7 3 5 4 2 1 6 8
3 8 2 5 4 6 7 1

Sample 2 Output

17517

Sample 3 Input

3
1 2 3
1 2 3

Sample 3 Output

0

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