Codeforces Round 852 (Div. 2)
C
Dora and Search
Codeforces
1200
原题
← BD →
翻译中…

As you know, the girl Dora is always looking for something. This time she was given a permutation, and she wants to find such a subsegment of it that none of the elements at its ends is either the minimum or the maximum of the entire subsegment. More formally, you are asked to find the numbers $l$ and $r$ $(1 \leq l \leq r \leq n)$ such that $a_l \neq \min(a_l, a_{l + 1}, \ldots, a_r)$, $a_l \neq \max(a_l, a_{l + 1}, \ldots, a_r)$ and $a_r \neq \min(a_l, a_{l + 1}, \ldots, a_r)$, $a_r \neq \max(a_l, a_{l + 1}, \ldots, a_r)$.

翻译中…

A permutation of length $n$ is an array consisting of $n$ distinct integers from $1$ to $n$ in any order. For example, $[2,3,1,5,4]$ is a permutation, but $[1,2,2]$ is not a permutation ($2$ occurs twice in the array) and $[1,3,4]$ is also not a permutation ($n=3$, but $4$ is present in the array).

翻译中…

Help Dora find such a subsegment, or tell her that such a subsegment does not exist.

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Input

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Each test consists of multiple test cases. The first line contains a single integer $t$ ($1 \leq t \leq 10^4$) — the number of test cases. Description of the test cases follows.

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For each test case, the first line contains one integer $n$ ($1 \leq n \leq 2 \cdot 10^5$) — the length of permutation.

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The second line contains $n$ distinct integers $a_1, a_2, \ldots, a_n$ ($1 \leq a_i \leq n$) — the elements of permutation.

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It is guarented that the sum of $n$ over all test cases doesn't exceed $2 \cdot 10^5$.

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Output

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For each test case, output $-1$ if the desired subsegment does not exist.

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Otherwise, output two indexes $l, r$ such that $[a_{l}, a_{l + 1}, \ldots, a_{r}]$ satisfies all conditions.

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If there are several solutions, then output any of them.

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Note

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In the first and fourth test cases, it can be shown that there are no desired subsegments.

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In the second test case, the subsegment $[1, 4]$ satisfies all the conditions, because $\max(a_1, a_2, a_3, a_4) = 4, \min(a_1, a_2, a_3, a_4) = 1$, as we see, all the conditions are met.

翻译中…

In the third test case, the subsegment $[2, 6]$ also satisfies all the conditions described.

翻译中…

样例

Input #1
4
3
1 2 3
4
2 1 4 3
7
1 3 2 4 6 5 7
6
2 3 6 5 4 1
Output #1
-1
1 4
2 6
-1
InputCopy OutputCopy
题目信息
题号
1793C
时间限制
1 s
内存限制
256 MB
标签
构造
数据结构
双指针

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。