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CF1990A.Submission Bait
Submission Bait
Alice and Bob are playing a game in an array of size .
They take turns to do operations, with Alice starting first. The player who can not operate will lose. At first, a variable is set to .
In one operation, a player can do:
- Choose an index () such that and set to . Then, set to .
Determine whether Alice has a winning strategy.
Input
The first line contains an integer () — the number of test cases.
For each test case:
- The first line contains an integer () — the size of the array.
- The second line contains integers () — the elements of the array.
Output
For each test case, if Alice has a winning strategy, output "YES". Otherwise, output "NO".
You can output the answer in any case (upper or lower). For example, the strings "yEs", "yes", "Yes", and "YES" will be recognized as positive responses.
Note
In the first test case, Alice can choose since .
After Alice's operation, and . Bob can not do any operation. Alice wins.
In the second test case, Alice doesn't have a winning strategy.
For example, if Alice chooses , after Alice's operation: and . Then, Bob can choose since . After Bob's operation: and . Alice can not do any operation. Bob wins.
Samples
5
2
2 1
2
1 1
3
3 3 3
4
3 3 4 4
4
1 2 2 2
YES
NO
YES
NO
YES
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