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CF1203A.Circle of Students
Circle of Students
There are students standing in a circle in some order. The index of the -th student is . It is guaranteed that all indices of students are distinct integers from to (i. e. they form a permutation).
Students want to start a round dance. A clockwise round dance can be started if the student comes right after the student in clockwise order (there are no students between them), the student comes right after the student in clockwise order, and so on, and the student comes right after the student in clockwise order. A counterclockwise round dance is almost the same thing — the only difference is that the student should be right after the student in counterclockwise order (this condition should be met for every from to ).
For example, if the indices of students listed in clockwise order are , then they can start a clockwise round dance. If the students have indices in clockwise order, then they can start a counterclockwise round dance.
Your task is to determine whether it is possible to start a round dance. Note that the students cannot change their positions before starting the dance; they cannot swap or leave the circle, and no other student can enter the circle.
You have to answer independent queries.
Input
The first line of the input contains one integer () — the number of queries. Then queries follow.
The first line of the query contains one integer () — the number of students.
The second line of the query contains a permutation of indices (), where is the index of the -th student (in clockwise order). It is guaranteed that all are distinct integers from to (i. e. they form a permutation).
Output
For each query, print the answer on it. If a round dance can be started with the given order of students, print "YES". Otherwise print "NO".
Samples
5
4
1 2 3 4
3
1 3 2
5
1 2 3 5 4
1
1
5
3 2 1 5 4
YES
YES
NO
YES
YES
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