Farmer John is building PLUSworld, a giant barn complex with $n$ barns numbered from $1$ to $n$. For each $1 \le i \le n$, there is currently a one-way walkway from barn $i$ to barn $a_i$.
Before opening PLUSworld, Farmer John wants to reconfigure the roads so that, for every $1 \le i \le n$, the road from barn $i$ points to barn $b_i$. The target roads have the special property that each road points to its own barn or to a higher-numbered barn $(i \le b_i)$.
To do this, he sends Bessie to one barn of his choice. Let $p$ be the barn where Bessie is currently located. Bessie may perform the following operations any number of times:
- Operation
$1$: Increase the destination of the road from the current barn by$1$. More formally, set$a_p := a_p + 1$. This operation may only be performed if$a_p \lt n$. - Operation
$2$: Follow the road from the current barn. More formally, set$p := a_p$.
Operation $1$ changes the array $a$, but Bessie stays at the same barn. Operation $2$ changes Bessie's current barn, but does not change the array.
Your goal is to make the array $a$ equal to the array $b$.
Determine whether this is possible. If it is possible, output any valid starting barn and any sequence of operations that makes $a=b$.
It can be shown that if a solution exists, then there exists one using at most $2n^2$ operations.
Input
Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 10^4$). The description of the test cases follows.
The first line of each test case contains a single integer $n$ ($1\le n\le 1000$).
The second line contains $n$ integers $a_1,a_2,\ldots,a_n$ ($1\le a_i\le n$).
The third line contains $n$ integers $b_1,b_2,\ldots,b_n$ ($\color{red}{i\le b_i}\le n$).
It is guaranteed that the sum of $n^2$ over all test cases does not exceed $1000^2$.
Output
For each test case, if it is impossible to make $a$ equal to $b$, output a single integer $-1$.
Otherwise, output two lines.
On the first line, output two integers $o$ and $p$ — the number of operations you will perform and the initial index you choose ($0 \leq o \leq 2n^2$, $1 \leq p \leq n$).
On the second line, output $o$ integers $c_1,c_2,\ldots,c_o$ ($1\le c_i\le 2$), where $c_i$ is the type of the $i$-th operation.
If $c_i=1$, you perform operation $1$ and set $a_p:=a_p+1$. This operation may only be used if $a_p \lt n$ at that moment.
If $c_i=2$, you perform operation $2$ and set $p:=a_p$.
After performing all $o$ operations, the array $a$ must be equal to $b$.
If there are multiple valid answers, you may output any of them.
Note
For the first test case, Bessie starts at barn $1$. She increases $a_1$ from $1$ to $2$, follows the road to barn $2$, and increases $a_2$ from $2$ to $3$. The resulting array is $[2,3,3]$, which is equal to $b$.
For the second test case, $a_1=2 \gt b_1=1$. Since road destinations can only be increased, it is impossible to make $a_1$ equal to $b_1$, so the answer is $-1$.
For the third test case, Bessie starts at barn $1$. She changes $a_1$ from $1$ to $2$ and follows the road to barn $2$. She then changes $a_2$ from $1$ to $3$ and moves to barn $3$, changes $a_3$ from $1$ to $4$ and moves to barn $4$, and finally changes $a_4$ from $4$ to $5$. The resulting array is $[2,3,4,5,5]$, which is equal to $b$.
样例
9
3
1 2 3
2 3 3
2
2 2
1 2
5
1 1 1 4 5
2 3 4 5 5
3
1 1 1
1 2 3
3
1 1 1
3 2 3
3
1 1 3
1 2 3
4
1 1 1 4
3 3 4 4
4
1 4 3 4
1 4 3 4
5
1 3 4 5 4
2 3 4 5 5
5 1
1 2 1 2 2
-1
12 1
1 2 1 1 2 1 1 1 2 1 2 2
-1
-1
2 2
1 2
12 1
1 1 2 1 2 1 1 2 1 1 2 2
0 1
7 1
1 2 2 2 2 1 2
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