import sys
readline = sys.stdin.readline

def kadomatsu(a, b, c):
    for i in [-1, 1]:
        if a * i < b * i and b * i > c * i and a != c:
            return True
    return False

def calc(A):
    N = len(A)
    inf = 10 ** 18
    dp = [-inf] * (N + 1)
    dp[0] = 0
    for i in range(N):
        if i != N - 1:
            dp[i + 1] = max(dp[i + 1], dp[i])
        if i < N - 2: 
            if kadomatsu(A[i], A[i + 1], A[i + 2]):
                dp[i + 3] = max(dp[i + 3], dp[i] + A[i])
    return max(dp)
    
    

T = int(readline())
for _ in range(T):
    N = int(readline())
    A = list(map(int, readline().split()))
    ans = calc(A)
    a = A.pop(0)
    A.append(a)
    ans = max(ans, calc(A))
    a = A.pop(0)
    A.append(a)
    ans = max(ans, calc(A))
    print(ans)