#include <bits/stdc++.h>

using namespace std;
const int MAXN = 1e5+10;
int b[MAXN];

int BinarySearch(int l, int r, int ans)
{
    int mid;
    while (l < r)
    {
        mid = (l+r)/2;
        if (b[mid] >= ans) r = mid;
        else l = mid;
    }
    return r;
}
int LongestIncreasingPath(int a[], int n)
{
    if (n == 0)return 0;
    memset(b, -1, sizeof(b));
    int b[MAXN], k = 1, i;
    b[0] = a[0];

    for (i = 0; i < n; i++)
    {
        if (a[i] < b[0])b[0] = a[i];
        else if (a[i] > b[k-1])b[k++] = a[i];
        else b[BinarySearch(-1, k-1, a[i])] = a[i];
    }
    return k;

}
int main()
{
    ifstream cin ("stairway.in");
    ofstream cout("stairway.out");
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    int t;
    cin >> t;

    while (t--)
    {
        int n, a[MAXN], i, x, k = 0, temp_br = 1, pr;
        cin >> n >> pr;
        for (i = 1; i < n; i++)
        {
            cin >> x;
            if (x == pr)temp_br++;
            else
            {
                if (temp_br > 1)
                {
                    a[k++] = pr;
                    temp_br = 1;
                }
            }
            pr = x;
        }
        if (temp_br > 1)a[k++] = pr;
        cout << LongestIncreasingPath(a, k)*2 << '\n';
    }
    return 0;
}
/*
10
1 1 1 1 1 1 2 2 1 1
*/