The only difference between easy and hard versions is constraints.

You are given a sequence a consisting of n positive integers.

Let's define a three blocks palindrome as the sequence, consisting of at most two distinct elements (let these elements are a and b, a can be equal b) and is as follows: [\underbrace{a, a, ..., a}_{x}, \underbrace{b, b, ..., b}_{y}, \underbrace{a, a, ..., a}_{x}]. There x, y are integers greater than or equal to 0. For example, sequences [], [2], [1, 1], [1, 2, 1], [1, 2, 2, 1] and [1, 1, 2, 1, 1] are three block palindromes but [1, 2, 3, 2, 1], [1, 2, 1, 2, 1] and [1, 2] are not.

Your task is to choose the maximum by length subsequence of a that is a three blocks palindrome.

You have to answer t independent test cases.

Recall that the sequence t is a a subsequence of the sequence s if t can be derived from s by removing zero or more elements without changing the order of the remaining elements. For example, if s=[1, 2, 1, 3, 1, 2, 1], then possible subsequences are: [1, 1, 1, 1], [3] and [1, 2, 1, 3, 1, 2, 1], but not [3, 2, 3] and [1, 1, 1, 1, 2].

Input

The first line of the input contains one integer t (1 ≤ t ≤ 2000) — the number of test cases. Then t test cases follow.

The first line of the test case contains one integer n (1 ≤ n ≤ 2000) — the length of a. The second line of the test case contains n integers a_1, a_2, ..., a_n (1 ≤ a_i ≤ 26), where a_i is the i-th element of a. Note that the maximum value of a_i can be up to 26.

It is guaranteed that the sum of n over all test cases does not exceed 2000 (∑ n ≤ 2000).

Output

For each test case, print the answer — the maximum possible length of some subsequence of a that is a three blocks palindrome.

Example

Input


6
8
1 1 2 2 3 2 1 1
3
1 3 3
4
1 10 10 1
1
26
2
2 1
3
1 1 1


Output


7
2
4
1
1
3
import java.util.*;
import java.io.*;
public class Main
{
    public static void main(String args[])throws Exception
    {
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        PrintWriter pw=new PrintWriter(System.out);
        int t=Integer.parseInt(br.readLine());
        for(int x=0;x<t;x++)
        {
            int n=Integer.parseInt(br.readLine());
            int arr[]=new int[n];
            String str[]=br.readLine().split(" ");
            for(int i=0;i<n;i++)
            arr[i]=Integer.parseInt(str[i]);
            int arrcntr[]=new int[27];
            for(int i=0;i<n;i++)
            arrcntr[arr[i]]++;
            int max=Integer.MIN_VALUE;
            for(int p=1;p<=26;p++)
            {
                if(arrcntr[p]>=2)
                {
                    for(int j=2;j<=arrcntr[p];j+=2)
                    {
                        int lcntr=0,rcntr=0,l=0,r=0;
                        int temparr[]=new int[27];
                        for(int i=0;i<n;i++)
                        {
                            if(arr[i]==p)
                            lcntr++;
                            if(lcntr==j/2)
                            {
                                l=i+1;
                                break;
                            }
                        }
                        for(int i=n-1;i>=0;i--)
                        {
                            if(arr[i]==p)
                            rcntr++;
                            if(rcntr==j/2)
                            {
                                r=i-1;
                                break;
                            }
                        }
                        //pw.println(l+" "+r);
                        for(int i=l;i<=r;i++)
                        temparr[arr[i]]++;
                        int maxcnt=-1;
                        for(int i=1;i<27;i++)
                        maxcnt=Math.max(maxcnt,temparr[i]);
                        max=Math.max(max,maxcnt+lcntr+rcntr);
                    }
                    //pw.println("In secondloop"+max+" "+maxcnt);
                }
            }
            for(int i=1;i<=26;i++)
            max=Math.max(max,arrcntr[i]);
            pw.println(max);
        }
        pw.flush();
        pw.close();
    }
}