Problem9705--ABC190 —— E - Magical Ornament

9705: ABC190 —— E - Magical Ornament

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

There are $N$ kinds of magical gems, numbered $1, 2, \ldots, N$, distributed in the AtCoder Kingdom.  
Takahashi is trying to make an ornament by arranging gems in a row.  
For some pairs of gems, we can put the two gems next to each other; for other pairs, we cannot. We have $M$ pairs for which the two gems can be adjacent: (Gem $A_1$, Gem $B_1$), (Gem $A_2$, Gem $B_2$), $\ldots$, (Gem $A_M$, Gem $B_M$). For the other pairs, the two gems cannot be adjacent. (Order does not matter in these pairs.)  
Determine whether it is possible to form a sequence of gems that has one or more gems of each of the kinds $C_1, C_2, \dots, C_K$. If the answer is yes, find the minimum number of stones needed to form such a sequence.

Input

Input is given from Standard Input in the following format:

```
$N$ $M$
$A_1$ $B_1$
$A_2$ $B_2$
$\hspace{7mm}\vdots$
$A_M$ $B_M$
$K$
$C_1$ $C_2$ $\cdots$ $C_K$
```

Output

Print the minimum number of stones needed to form a sequence of gems that has one or more gems of each of the kinds $C_1, C_2, \dots, C_K$.  
If such a sequence cannot be formed, print `-1` instead.

Constraints

-   All values in input are integers.
-   $1 ≤ N ≤ 10^5$
-   $0 ≤ M ≤ 10^5$
-   $1 ≤ A_i < B_i ≤ N$
-   If $i ≠ j$, $(A_i, B_i) ≠ (A_j, B_j)$.
-   $1 ≤ K ≤ 17$
-   $1 ≤ C_1 < C_2 < \dots < C_K ≤ N$

Sample 1 Input

4 3
1 4
2 4
3 4
3
1 2 3

Sample 1 Output

5
For example, by arranging the gems in the order [1,4,2,4,3], we can form a sequence of length 5 with Gems 1,2,3.

Sample 2 Input

4 3
1 4
2 4
1 2
3
1 2 3

Sample 2 Output

-1

Sample 3 Input

10 10
3 9
3 8
8 10
2 10
5 8
6 8
5 7
6 7
1 6
2 4
4
1 2 7 9

Sample 3 Output

11
For example, by arranging the gems in the order [1,6,7,5,8,3,9,3,8,10,2], we can form a sequence of length 11 with Gems 1,2,7,9.

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