class SegmentTree(object):
    def __init__(self, A, dot, unit):
        n = 1 << (len(A) - 1).bit_length()
        tree = [unit] * (2 * n)
        for i, v in enumerate(A):
            tree[i + n] = v
        for i in range(n - 1, 0, -1):
            tree[i] = dot(tree[i << 1], tree[i << 1 | 1])
        self._n = n
        self._tree = tree
        self._dot = dot
        self._unit = unit

    def __getitem__(self, i):
        return self._tree[i + self._n]

    def update(self, i, v):
        i += self._n
        self._tree[i] = v
        while i != 1:
            i >>= 1
            self._tree[i] = self._dot(self._tree[i << 1], self._tree[i << 1 | 1])

    def add(self, i, v):
        self.update(i, self[i] + v)

    def sum(self, l, r): #これで[l,r)から取り出す。
        l += self._n
        r += self._n
        l_val = r_val = self._unit
        while l < r:
            if l & 1:
                l_val = self._dot(l_val, self._tree[l])
                l += 1
            if r & 1:
                r -= 1
                r_val = self._dot(self._tree[r], r_val)
            l >>= 1
            r >>= 1
        return self._dot(l_val, r_val)

def check(X):
    if X[0] == X[1] or X[1] == X[2] or X[2] == X[0]:
        return False
    if X[0] < X[1] and X[1] > X[2]:
        return True
    if X[0] > X[1] and X[1] < X[2]:
        return True
    return False

T = int(input()); INF = 1 << 60
for _ in range(T):
    N = int(input())
    A = list(map(int,input().split()))
    ans = 0
    for i in range(3):
        if i >= 1:
            temp = A[0]
            A = A[1:]
            A.append(temp)
        zero = [0]*(N+1)
        dp = SegmentTree(zero,max,0)
        for j in range(N-2): #0-N-2
            #print(A[j:j+3])
            if check(A[j:j+3]):
                #print("A",A[j:j+3],A[j])
                dp.update(j+1, A[j] + dp.sum(0,j-1)) #j+1(0-indexでj)番目を更新
                #print(dp.__getitem__(j+1),"koushin")
        ##print
        #for k in range(N+1):
        #    print(dp.__getitem__(k))
        ans = max(ans,dp.sum(0,N+1))
    print(ans)