Problem H. Hills And Valleys

时间限制 1000 ms   内存限制 256 MB

Tauren has an integer sequence $A$ of length $n$ (1-based). He wants you to invert an interval $[l, r]$ $(1 \leq l \leq r \leq n)$ of $A$ (i.e. replace $A_l, A_{l + 1}, \cdots, A_r$ with $A_r, A_{r - 1}, \cdots, A_l$) to maximize the length of the longest non-decreasing subsequence of $A$. Find that maximal length and any inverting way to accomplish that mission.
A non-decreasing subsequence of $A$ with length $m$ could be represented as $A_{x_1}, A_{x_2}, \cdots, A_{x_m}$ with $1 \leq x_1 < x_2 < \cdots < x_m \leq n$ and $A_{x_1} \leq A_{x_2} \leq \cdots \leq A_{x_m}$.
 

输入数据

The first line contains one integer $T$, indicating the number of test cases.
The following lines describe all the test cases. For each test case:
The first line contains one integer $n$.
The second line contains $n$ integers $A_1, A_2, \cdots, A_n$ without any space.
$1 \leq T \leq 100$, $1 \leq n \leq 10^5$, $0 \leq A_i \leq 9$ $(i = 1, 2, \cdots, n)$.
It is guaranteed that the sum of $n$ in all test cases does not exceed $2 \cdot 10^5$.
 

输出数据

For each test case, print three space-separated integers $m, l$ and $r$ in one line, where $m$ indicates the maximal length and $[l, r]$ indicates the relevant interval to invert.
 

样例输入

复制
2
9
864852302
9
203258468

样例输出

复制
5 1 8
6 1 2

样例说明

 In the first example, 864852302 after inverting [1, 8] is 032584682, one of the longest non-decreasing subsequences of which is 03588. In the second example, 203258468 after inverting [1, 2] is 023258468, one of the longest non-decreasing subsequences of which is 023588. 
         
 

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