#include<iostream>
#include<cstring>
#include<cstdio>
#include<algorithm>
using namespace std;

int a[100005],n,m,has[15];

int main()
{
    int T;
    scanf("%d",&T);
    while(T--)
    {
        memset(has,0,sizeof(has));
        scanf("%d%d",&n,&m);
        int cnt = 0;
        for(int i = 1;i <= n;i++)
        {
            scanf("%d",&a[i]);
            if(!has[a[i]])    has[a[i]] = 1;
        }
        int ans = 0;
        for(int i = 1;i <= m;i++)
        {
            for(int j = 1;j <= m;j++)
            {
                if(i == j)    continue;
                if(!has[i] || !has[j])    continue;
                int sum = 0,maxx = 0,flag = 0;
                for(int k = 1;k <= n;k++)
                {
                    if(a[k] == i)    sum++;
                    else if(a[k] == j)
                    {
                        sum--;
                        flag = 1;
                    }
                    if(sum < 0)
                    {
                        sum = 0;
                        flag = 0;
                    }
                    if(flag)    maxx = max(maxx,sum);
                    else    maxx = max(maxx,sum-1);
                }
                ans = max(ans,maxx);
            }
        }
        printf("%d\n",ans);
    }
    return 0;
}