#include<bits/stdc++.h>
using namespace std;
using LL=long long;
using ULL=unsigned long long;
#define rep(i,n) for(int i=0; i<(n); i++)

bool iskadomatsu(int a,int b,int c){
  if(a==b||b==c||a==c) return false;
  return ((a<b&&c<b)||(a>b&&c>b));
}

int N;
int A[200004];
bool K[200002];
LL dp[200005];

void loop(){
  scanf("%d",&N);
  rep(i,N) scanf("%d",&A[i]);
  rep(i,4) A[N+i]=A[i];
  rep(i,N+2) K[i]=iskadomatsu(A[i],A[i+1],A[i+2]);
  LL ans=0;
  rep(s,3){
    rep(i,N+5) dp[i]=0;
    rep(i,N){
      dp[i+1]=max(dp[i+1],dp[i]);
      if(K[i+s]) dp[i+3]=max(dp[i+3],dp[i]+A[i+s]);
    }
    ans=max(ans,dp[N]);
  }
  printf("%lld\n",ans);
}

int main(){
  int T; scanf("%d",&T);
  while(T--) loop();
  return 0;
}