Sukarako's Field Trip

#include <bits/stdc++.h>
using namespace std;
mt19937_64 RNG(chrono::steady_clock::now().time_since_epoch().count());
#define NeedForSpeed                  \
    ios_base::sync_with_stdio(false); \
    cin.tie(NULL);                    \
    cout.tie(NULL);
#define int long long
#define all(x) (x).begin(), (x).end()
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<vi> vvi;
typedef vector<pair<int, int>> vpi;
#define f first
#define s second
#define endl "\n"
const int mod = 1000000007;
int gcd(int a, int b) { return b == 0 ? a : gcd(b, a % b); }
void solve()
{
    int n;
    cin >> n;
    vi a(n);
    for (int i = 0; i < n; i++)
    {
        cin >> a[i];
    }
    deque<int> v;
    if (n % 2 == 1)
    {
        // Odd case
        v.push_back(a[n / 2]);
        for (int i = 1; i <= n / 2; i++)
        {
            if (v.front() == a[n / 2 - i])
            {
                v.push_back(a[n / 2 - i]);
                v.push_front(a[n / 2 + i]);
            }
            else if (v.back() == a[n / 2 + i])
            {
                v.push_back(a[n / 2 - i]);
                v.push_front(a[n / 2 + i]);
            }
            else
            {
                v.push_back(a[n / 2 + i]);
                v.push_front(a[n / 2 - i]);
            }
        }
    }
    else
    {
        // Even case
        v.push_back(a[n / 2]);
        v.push_back(a[n / 2 - 1]);
        for (int i = 1; i < n / 2; i++)
        {
            if (v.front() == a[n / 2 - 1 - i])
            {
                v.push_back(a[n / 2 - 1 - i]);
                v.push_front(a[n / 2 + i]);
            }
            else if (v.back() == a[n / 2 + i])
            {
                v.push_back(a[n / 2 - 1 - i]);
                v.push_front(a[n / 2 + i]);
            }
            else
            {
                v.push_back(a[n / 2 + i]);
                v.push_front(a[n / 2 - 1 - i]);
            }
        }
    }
    int cnt = 0;
    for (int i = 0; i < n - 1; i++)
    {
        if (v[i] == v[i + 1])
        {
            cnt++;
        }
    }
    cout << cnt << endl;
}

signed main()
{
    NeedForSpeed;
    int t = 1;
    cin >> t;
    while (t--)
    {
        solve();
    }
    return 0;
}