Almost Triple Deletions solution codeforces-

Almost Triple Deletions solution codeforces-

You are given an integer n and an array 1,2,,a1,a2,…,an.

In one operation, you can choose an index i (1<1≤i<n) for which +1ai≠ai+1 and delete both ai and +1ai+1 from the array. After deleting ai and +1ai+1, the remaining parts of the array are concatenated.

For example, if =[1,4,3,3,6,2]a=[1,4,3,3,6,2], then after performing an operation with =2i=2, the resulting array will be [1,3,6,2][1,3,6,2].

What is the maximum possible length of an array of equal elements obtainable from a by performing several (perhaps none) of the aforementioned operations?

Input

Each test contains multiple test cases. The first line of input contains one integer t (110001≤t≤1000) — the number of test cases. The following lines contain the descriptions of the test cases.

The first line of each test case contains a single integer n (150001≤n≤5000) — the length of array a.

The second line of each test case contains n integers 1,2,,a1,a2,…,an (11≤ai≤n) — the elements of array a.

It is guaranteed that the sum of n across all test cases does not exceed 1000010000.

Output

For each testcase, print a single integer, the maximum possible length of an array of equal elements obtainable from a by performing a sequence of operations.

Example

input

Copy
5
7
1 2 3 2 1 3 3
1
1
6
1 1 1 2 2 2
8
1 1 2 2 3 3 1 1
12
1 5 2 3 3 3 4 4 4 4 3 3

output

Copy
3
1
0
4
2
Note

For the first testcase, an optimal sequence of operations would be: [1,2,3,2,1,3,3][3,2,1,3,3][3,3,3][1,2,3,2,1,3,3]→[3,2,1,3,3]→[3,3,3].

For the second testcase, all elements in the array are already equal.

For the third testcase, the only possible sequence of operations is: [1,1,1,2,2,2][1,1,2,2][1,2][][1,1,1,2,2,2]→[1,1,2,2]→[1,2]→[]. Note that, according to the statement, the elements deleted at each step must be different.

For the fourth testcase, the optimal sequence of operations is: [1,1,2,2,3,3,1,1][1,1,2,3,1,1][1,1,1,1][1,1,2,2,3,3,1,1]→[1,1,2,3,1,1]→[1,1,1,1].

For the fifth testcase, the only reachable array of two equal elements is [4,4][4,4].

Solution – CLICK HERE

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