#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <cmath>
#include <map>
#include <queue>
#include <iomanip>
#include <set>
#include <tuple>
#define mkp make_pair
#define mkt make_tuple
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define all(v) v.begin(),v.end()
using namespace std;
typedef long long ll;
const ll MOD=1e9+7;
template<class T> void chmin(T &a,const T &b){if(a>b) a=b;}
template<class T> void chmax(T &a,const T &b){if(a<b) a=b;}

const ll INF=1e18;

void solve(){
  int N;
  cin>>N;
  vector<ll> A(N);
  rep(i,N) cin>>A[i];

  ll ans=0;
  for(int k=0;k<3;k++){
    vector<ll> B;
    for(int i=k;i<N;i++) B.push_back(A[i]);
    for(int i=0;i<k;i++) B.push_back(A[i]);

    auto check = [](int a,int b,int c){
      if(a==b||b==c||c==a) return false;
      if(a<b&&b>c) return true;
      if(a>b&&b<c) return true;
      return false;
    };

    vector<ll> dp(N+1,-INF);
    dp[0]=0;
    for(int i=0;i<N;i++){
      chmax(dp[i+1],dp[i]);
      if(i+2<N&&check(B[i],B[i+1],B[i+2])) chmax(dp[i+3],dp[i]+B[i]);
    }
    chmax(ans,dp[N]);
  }
  cout<<ans<<"\n";
}

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);

  int T;
  cin>>T;
  rep(i,T) solve();

  return 0;
}