#include <bits/stdc++.h>
using namespace std;
typedef signed long long ll;

#define _P(...) (void)printf(__VA_ARGS__)
#define FOR(x,to) for(x=0;x<(to);x++)
#define FORR(x,arr) for(auto& x:arr)
#define FORR2(x,y,arr) for(auto& [x,y]:arr)
#define ALL(a) (a.begin()),(a.end())
#define ZERO(a) memset(a,0,sizeof(a))
#define MINUS(a) memset(a,0xff,sizeof(a))
template<class T> bool chmax(T &a, const T &b) { if(a<b){a=b;return 1;}return 0;}
template<class T> bool chmin(T &a, const T &b) { if(a>b){a=b;return 1;}return 0;}
//-------------------------------------------------------

int T;
int N,A[202020];
ll S[202020];

void solve() {
	int i,j,k,l,r,x,y; string s;
	
	cin>>T;
	while(T--) {
		cin>>N;
		FOR(i,N) cin>>A[i];
		A[N]=A[0];
		A[N+1]=A[1];
		ll ma=0;
		FOR(i,3) {
			FOR(j,N+5) S[j]=0;
			ll cur=0;
			for(j=i+2;j<i+N;j++) {
				S[j]=S[j-1];
				if(A[j-2]!=A[j-1]&&A[j-2]!=A[j-0]&&A[j-1]!=A[j-0]) {
					if((A[j-2]<A[j-1])==(A[j-0]<A[j-1])) S[j]=max(S[j],S[j-3]+A[j-2]);
				}
				ma=max(ma,S[j]);
			}
		}
		cout<<ma<<endl;
	}
}


int main(int argc,char** argv){
	string s;int i;
	if(argc==1) ios::sync_with_stdio(false), cin.tie(0);
	FOR(i,argc-1) s+=argv[i+1],s+='\n'; FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin);
	cout.tie(0); solve(); return 0;
}