#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
using ll = long long;
constexpr int INF = 0x3f3f3f3f;
constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr double EPS = 1e-8;
constexpr int MOD = 1000000007;
// constexpr int MOD = 998244353;
constexpr int dy[] = {1, 0, -1, 0}, dx[] = {0, -1, 0, 1};
constexpr int dy8[] = {1, 1, 0, -1, -1, -1, 0, 1}, dx8[] = {0, -1, -1, -1, 0, 1, 1, 1};
template <typename T, typename U> inline bool chmax(T &a, U b) { return a < b ? (a = b, true) : false; }
template <typename T, typename U> inline bool chmin(T &a, U b) { return a > b ? (a = b, true) : false; }
struct IOSetup {
  IOSetup() {
    std::cin.tie(nullptr);
    std::ios_base::sync_with_stdio(false);
    std::cout << fixed << setprecision(20);
  }
} iosetup;

bool is_kadomatsu(ll a, ll b, ll c) {
  return a != b && b != c && c != a && !(a < b && b < c) && !(a > b && b > c);
}

int main() {
  int t; cin >> t;
  while (t--) {
    int n; cin >> n;
    vector<int> a(n); REP(i, n) cin >> a[i];
    ll ans = 0;
    REP(_, 3) {
      vector<ll> dp(n, -LINF);
      REP(i, 2) dp[i] = 0;
      FOR(i, 2, n + 1) {
        if (is_kadomatsu(a[i - 2], a[i - 1], a[i])) chmax(dp[i], (i < 3 ? 0 : dp[i - 3]) + a[i - 2]);
        chmax(dp[i], dp[i - 1]);
      }
      chmax(ans, dp[n - 1]);
      a.emplace_back(a.front());
      a.erase(a.begin());
    }
    cout << ans << '\n';
  }
  return 0;
}