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{
    static class InputReader {

        private final InputStream stream;
        private final byte[] buf = new byte[8192];
        private int curChar, snumChars;
        private SpaceCharFilter filter;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        public int snext() {
            if (snumChars == -1)
                throw new InputMismatchException();
            if (curChar >= snumChars) {
                curChar = 0;
                try {
                    snumChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (snumChars <= 0)
                    return -1;
            }
            return buf[curChar++];
        }

        public int nextInt() {
            int c = snext();
            while (isSpaceChar(c)) {
                c = snext();
            }
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = snext();
            }
            int res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = snext();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public long nextLong() {
            int c = snext();
            while (isSpaceChar(c)) {
                c = snext();
            }
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = snext();
            }
            long res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = snext();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public int[] nextIntArray(int n) {
            int a[] = new int[n];
            for (int i = 0; i < n; i++) {
                a[i] = nextInt();
            }
            return a;
        }

        public String readString() {
            int c = snext();
            while (isSpaceChar(c)) {
                c = snext();
            }
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = snext();
            } while (!isSpaceChar(c));
            return res.toString();
        }

        public String nextLine() {
            int c = snext();
            while (isSpaceChar(c))
                c = snext();
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = snext();
            } while (!isEndOfLine(c));
            return res.toString();
        }

        public boolean isSpaceChar(int c) {
            if (filter != null)
                return filter.isSpaceChar(c);
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        private boolean isEndOfLine(int c) {
            return c == '\n' || c == '\r' || c == -1;
        }

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);
        }

    }
    static class OutputWriter {
		private final PrintWriter writer;
 
		public OutputWriter(OutputStream outputStream) {
			writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
		}
 
		public OutputWriter(Writer writer) {
			this.writer = new PrintWriter(writer);
		}
 
		public void print(Object...objects) {
			for (int i = 0; i < objects.length; i++) {
				if (i != 0)
					writer.print(' ');
				writer.print(objects[i]);
			}
		}
 
		public void printLine(Object...objects) {
			print(objects);
			writer.println();
		}
 
		public void close() {
			writer.close();
		}
 
		public void flush() {
			writer.flush();
		}
 
		}
 
    static class IOUtils {
 
		public static int[] readIntArray(InputReader in, int size) {
            int[] array = new int[size];
            for (int i = 0; i < size; i++)
                array[i] = in.nextInt();
            return array;
        }

    }
    static int gcd(int a, int b) 
    { 
        if (a == 0) 
            return b; 
        return gcd(b % a, a); 
    } 
    
    static List<List<Integer>> occ;
    static int res;
    public static void solve(List<Integer> v)
    {
        
        int l =0, r = v.size()-1;
        int x = 0, s=0;
        for(int a:v)
        {
            s+=a;
        }
        res = Math.max(s,res);
        while(true)
        {
            boolean bl=false,br=false;
            x++;
            while(l<=r && !bl)
            {
                if(v.get(l)==0)
                {
                    bl = true;
                }
                else{
                    s--;
                }
                l++;
            }
            while(l<=r && !br)
            {
                if(v.get(r)==0)
                {
                    br = true;
                }
                else{
                    s--;
                }
                r--;
            }
            if(!bl || !br)
            {
                break;
            }
            res = Math.max(res,2*x+s);
        }
    }
    public static void main(String[] args) {
        InputReader in = new InputReader(System.in);
        OutputWriter out = new OutputWriter(System.out);
        //IOUtils io = new IOUtils();
        int t = in.nextInt();
        while(t-- > 0)
        {
            occ = new ArrayList<>();
            for(int i=0;i<200;i++)
            {
                occ.add(new ArrayList<>());
            }
            int n = in.nextInt();
            int[] arr = new int[n];
            for(int i=0;i<n;i++)
            {
                arr[i] = in.nextInt();
            }
            for(int i=0;i<n;i++)
            {
                occ.get(arr[i]-1).add(i);
            }
            res = 0; 
           // out.printLine(occ);
            for(int a=0;a<200;a++)
            {
                if(occ.get(a).isEmpty())
                    continue;
                for(int b=0;b<200;b++)
                {
                    if(a==b)
                    {
                        res = Math.max(occ.get(a).size(),res);
                        continue;
                    }
                    List<Integer> v = new ArrayList<>();
                    int i = 0,j=0;
                    while(i<occ.get(a).size() && j<occ.get(b).size())
                    {
                        if(occ.get(a).get(i)<occ.get(b).get(j))
                        {
                            v.add(0);
                            i++;
                        }
                        else{
                            v.add(1);
                            j++;
                        }
                    }
                    while(i<occ.get(a).size())
                    {
                        v.add(0);
                        i++;
                    }
                    while(j<occ.get(b).size())
                    {
                        v.add(1);
                        j++;
                    }
                    //out.printLine(v);
                    solve(v);
                }   
            }
            out.printLine(res);
        }
        out.flush();
        out.close();
    }
}