/* Problem URL: https://codeforces.com/problemset/problem/2033/C */ #include #include #include using namespace std; using namespace __gnu_pbds; template > using ordered_set = tree; #define V vector #define rmin(a, b) a = min(a, b) #define rmax(a, b) a = max(a, b) #define rep(i, lim) for (int i = 0; i < (lim); i++) #define nrep(i, s, lim) for (int i = s; i < (lim); i++) #define repv(i, v) for (auto &i : (v)) #define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; } #define sortv(v) sort(v.begin(), v.end()) #define all(v) (v).begin(), (v).end() using vi = vector; using vvi = vector; using vvvi = vector; using vvvvi = vector; using ll = long long; using vl = vector; using vvl = vector; using vvvl = vector; using vvvvl = vector; template auto operator<<(ostream &os, const vector &vec)->ostream& { os << vec[0]; for (size_t i = 1; i < vec.size(); i++) { os << ' ' << vec[i]; } os << '\n'; return os; } template auto operator>>(istream &is, vector &vec)->istream& { for (auto &i : vec) { is >> i; } return is; } template auto operator<<(ostream &os, const vector> &vec)->ostream& { for (auto &i : vec) { os << i[0]; for (size_t j = 1; j < i.size(); j++) { os << ' ' << i[j]; } os << '\n'; } return os; } template auto operator>>(istream &is, vector> &vec)->istream& { for (auto &i : vec) { for (auto &j : i) { is >> j; } } return is; } const int oo = INT32_MAX >> 1; const ll OO = INT64_MAX >> 1; void pre() { } #define TEST 1 void solve() { int n; cin >> n; vi a(n); cin >> a; vvi dp(n >> 1, vi(2)); nrep(i, 1, n >> 1) { dp[i][0] = min(dp[i - 1][0] + (a[i] == a[i - 1]) + (a[n - i - 1] == a[n - i]), dp[i - 1][1] + (a[i] == a[n - i]) + (a[n - i - 1] == a[i - 1])); dp[i][1] = min(dp[i - 1][0] + (a[n - i - 1] == a[i - 1]) + (a[i] == a[n - i]), dp[i - 1][1] + (a[n - i - 1] == a[n - i]) + (a[i] == a[i - 1])); } int add = 0; if (n & 1) { add = (a[n >> 1] == a[(n >> 1) + 1]) + (a[n >> 1] == a[(n >> 1) - 1]); } else { add = (a[n >> 1] == a[(n >> 1) - 1]); } cout << min(dp.back()[0], dp.back()[1]) + add << '\n'; } int main() { ios::sync_with_stdio(false); cin.tie(nullptr); pre(); int t; (TEST && cin >> t) || (t = 1); while (t--) { solve(); } }