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CF1706B.Making Towers
Making Towers
You have a sequence of colored blocks. The color of the -th block is , an integer between and .
You will place the blocks down in sequence on an infinite coordinate grid in the following way.
- Initially, you place block at .
- For , if the -th block is placed at position , then the -th block can be placed at one of positions , , (but not at position ), as long no previous block was placed at that position.
A tower is formed by blocks such that they are placed at positions for some position and integer . The size of the tower is , the number of blocks in it. A tower of color is a tower such that all blocks in it have the color .
For each color from to , solve the following problem independently:
- Find the maximum size of a tower of color that you can form by placing down the blocks according to the rules.
Input
The first line contains a single integer () — the number of test cases.
The first line of each test case contains a single integer ().
The second line of each test case contains integers ().
It is guaranteed that the sum of over all test cases does not exceed .
Output
For each test case, output integers. The -th of them should be the maximum size of an tower of color you can form by following the given rules. If you cannot form any tower of color , the -th integer should be .
Note
In the first test case, one of the possible ways to form a tower of color and size is:
- place block at position ;
- place block to the right of block , at position ;
- place block above block , at position ;
- place block to the left of block , at position ;
- place block to the left of block , at position ;
- place block above block , at position ;
- place block to the right of block , at position .

The blocks at positions , , and all have color , forming an tower of size .
In the second test case, note that the following placement is not valid, since you are not allowed to place block under block :

It can be shown that it is impossible to form a tower of color and size .
Samples
6
7
1 2 3 1 2 3 1
6
4 2 2 2 4 4
1
1
5
5 4 5 3 5
6
3 3 3 1 3 3
8
1 2 3 4 4 3 2 1
3 2 2 0 0 0 0
0 3 0 2 0 0
1
0 0 1 1 1
1 0 4 0 0 0
2 2 2 2 0 0 0 0
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