private static int[] dp;
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int t = in.nextInt();
while (t-- > 0) {
int N = in.nextInt();
dp = new int[N];
int[] values = new int[N];
for (int i = 0; i < N; i++) {
values[i] = in.nextInt();
}
System.out.println(Math.max(sell(values, 0, N - 2), sell(values, 1, N - 1)));
}
}
private static int sell(int[] values, int first, int last) {
if (last - first == 0) return values[first];
if (last - first == 1) return Math.max(values[first], values[last]);
dp[first] = values[first];
dp[first + 1] = values[first + 1];
dp[first + 2] = values[first] + values[first + 2];
for (int i = first + 3; i <= last; i++) {
dp[i] = Math.max(dp[i - 2], dp[i - 3]) + values[i];
}
return Math.max(dp[last], dp[last - 1]);
}