CF1420A.Cubes Sorting

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题目描述

For god's sake, you're boxes with legs! It is literally your only purpose! Walking onto buttons! How can you not do the one thing you were designed for?Oh, that's funny, is it? Oh it's funny? Because we've been at this for twelve hours and you haven't solved it either, so I don't know why you're laughing. You've got one hour! Solve it!

Wheatley decided to try to make a test chamber. He made a nice test chamber, but there was only one detail absent — cubes.

For completing the chamber Wheatley needs nn cubes. ii -th cube has a volume aia_i .

Wheatley has to place cubes in such a way that they would be sorted in a non-decreasing order by their volume. Formally, for each i>1i>1 , ai1aia_{i-1} \le a_i must hold.

To achieve his goal, Wheatley can exchange two neighbouring cubes. It means that for any i>1i>1 you can exchange cubes on positions i1i-1 and ii .

But there is a problem: Wheatley is very impatient. If Wheatley needs more than n(n1)21\frac{n \cdot (n-1)}{2}-1 exchange operations, he won't do this boring work.

Wheatly wants to know: can cubes be sorted under this conditions?

输入格式

Each test contains multiple test cases.

The first line contains one positive integer tt ( 1t10001 \le t \le 1000 ), denoting the number of test cases. Description of the test cases follows.

The first line of each test case contains one positive integer nn ( 2n51042 \le n \le 5 \cdot 10^4 ) — number of cubes.

The second line contains nn positive integers aia_i ( 1ai1091 \le a_i \le 10^9 ) — volumes of cubes.

It is guaranteed that the sum of nn over all test cases does not exceed 10510^5 .

输出格式

For each test case, print a word in a single line: "YES" (without quotation marks) if the cubes can be sorted and "NO" (without quotation marks) otherwise.

输入输出样例

  • 输入#1

    3
    5
    5 3 2 1 4
    6
    2 2 2 2 2 2
    2
    2 1

    输出#1

    YES
    YES
    NO

说明/提示

In the first test case it is possible to sort all the cubes in 77 exchanges.

In the second test case the cubes are already sorted.

In the third test case we can make 00 exchanges, but the cubes are not sorted yet, so the answer is "NO".

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