CodeTON Round 7 (Div. 1 + Div. 2, Rated, Prizes!)
A
Jagged Swaps
Codeforces
800
原题
←B →
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You are given a permutation$^\dagger$ $a$ of size $n$. You can do the following operation

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  • Select an index $i$ from $2$ to $n - 1$ such that $a_{i - 1} \lt a_i$ and $a_i \gt a_{i+1}$. Swap $a_i$ and $a_{i+1}$.
翻译中…

Determine whether it is possible to sort the permutation after a finite number of operations.

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$^\dagger$ A permutation is an array consisting of $n$ distinct integers from $1$ to $n$ in arbitrary order. For example, $[2,3,1,5,4]$ is a permutation, but $[1,2,2]$ is not a permutation ($2$ appears twice in the array) and $[1,3,4]$ is also not a permutation ($n=3$ but there is $4$ in the array).

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Input

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Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 5000$). Description of the test cases follows.

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The first line of each test case contains a single integer $n$ ($3 \le n \le 10$) — the size of the permutation.

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The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($1 \le a_i \le n$) — the elements of permutation $a$.

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Output

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For each test case, print "YES" if it is possible to sort the permutation, and "NO" otherwise.

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You may print each letter in any case (for example, "YES", "Yes", "yes", "yEs" will all be recognized as positive answer).

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Note

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In the first test case, the permutation is already sorted.

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In the second test case, we can choose index $i=2$ as $1 \lt 3$ and $3 \gt 2$ to form $[1, 2, 3, 5, 4]$. Then, we can choose index $i=4$ as $3 \lt 5$ and $5 \gt 4$ to form $[1, 2, 3, 4, 5]$.

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In the third test case, it can be proven that it is impossible to sort the permutation.

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样例

Input #1
6
3
1 2 3
5
1 3 2 5 4
5
5 4 3 2 1
3
3 1 2
4
2 3 1 4
5
5 1 2 3 4
Output #1
YES
YES
NO
NO
NO
NO
InputCopy OutputCopy
题目信息
题号
1896A
时间限制
1 s
内存限制
256 MB
标签
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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。