for _ in range(int(input())):
    N = int(input())
    A = list(map(int, input().split()))

    cum = [0]
    for a in A:
        cum.append(cum[-1]+a)
    MIN = [cum[-1]]
    MAX = [cum[-1]]
    for i in reversed(range(1, N)):
        MIN.append(min(MIN[-1], cum[i]))
        MAX.append(max(MAX[-1], cum[i]))
    MIN = MIN[::-1]
    MAX = MAX[::-1]

    ans = 0
    for i in range(N-2):
        cumL = cum[i+1]
        cumR = cum[-1]-cum[i+1]
        minSUM = MIN[i+1]-cumL
        maxSUM = MAX[i+1]-cumL
        ans = max(ans, cumL+max(abs(minSUM)+abs(cumR-minSUM), abs(maxSUM)+abs(cumR-maxSUM)))
    
    print(ans)