Codeforces Global Round 26
G
Magic Trick II
Codeforces
3200
原题
← FH →
翻译中…

The secret behind Oscar's first magic trick has been revealed! Because he still wants to impress Lura, he comes up with a new idea: he still wants to sort a permutation $p_1, p_2, \ldots, p_n$ of $[1, 2, \ldots, n]$.

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This time, he chooses an integer $k$. He wants to sort the permutation in non-decreasing order using the following operation several times:

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  1. Pick a continuous subarray of length $k$ and remove it from $p$.
  2. Insert the continuous subarray back into $p$ at any position (perhaps, in the very front or the very back).
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To be as impressive as possible, Oscar would like to choose the maximal value of $k$ such that he can sort his permutation. Please help him find the maximal $k$ as well as a sequence of operations that will sort the permutation. You don't need to minimize the number of operations, but you are allowed to use at most $5n^2$ operations.

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We have a proof that, for the maximal $k$ such that you can sort the permutation in any number of operations, you can also sort it in at most $5n^2$ operations.

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Input

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The first line contains a single integer $t$ ($1 \leq t \leq 10^3$) — the number of test cases.

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The first line of each test case contains a single integer $n$ ($5 \leq n \leq 10^3$) — the length of the permutation.

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The second line of each test case contains a permutation $p_1, p_2, \ldots, p_n$ of $[1, 2, \ldots, n]$.

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The sum of $n$ over all test cases does not exceed $2 \cdot 10^3$.

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Output

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For each test case, first output the chosen value of $k$ on a new line ($1 \leq k \leq n$).

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Then, output a single integer $m$ — the number of operations used ($0 \leq m \leq 5n^2$).

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Then, on each of the next $m$ lines, output the operations denoted by two integers $i$ and $j$ ($1 \leq i, j \leq n - k + 1$), representing an operation where you remove the subarray starting from index $i$ and replace it back into $p$ at index $j$.

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Note

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In the first test case, it is enough to move the last four numbers to the front.

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In the second test case, it can be shown that we cannot have $k = 4$ or $k = 5$. With $k = 3$, we can move the first three numbers to the end, and then the middle three to the front to sort the permutation.

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In the third test case, the permutation is already sorted. We can have $k = 6$ and use no operations.

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样例

Input #1
3
5
5 1 2 3 4
5
2 3 5 4 1
6
1 2 3 4 5 6
Output #1
4
1
2 1
3
2
1 3
2 1
6
0
InputCopy OutputCopy
题目信息
题号
1984G
时间限制
2 s
内存限制
256 MB
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题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。