#include <bits/stdc++.h>
using namespace std;
#define int long long
const int N = 1e6 + 10;
int a[N], f[N];
signed main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int Case;
    cin >> Case;
    while (Case--) {
        int n;
        cin >> n;
        for (int i = 1; i <= n; ++i) {
            cin >> a[i];
        }
        f[0] = 0;
        f[1] = a[1];
        f[2] = max(a[1], a[2]);
        if (n <= 2) {
            cout << f[n] << endl;
            continue;
        }
        for (int i = 3; i <= n; ++i) {
            f[i] = f[i - 2] + a[i];
            f[i] = max(f[i], f[i - 3] + a[i] + min(a[i - 1], a[i - 2]));
        }
        int ans = max({f[n], f[n - 1], f[n - 2] + min(a[n], a[n - 1])});
        cout << ans << endl;
    }
    return 0;
}