T = int(input())
for _ in range(T):
    N = int(input())
    A = [0]+list(map(int,input().split()))
    if sum(A)<0:
        A = [-a for a in A]
    Ind = []
    amin = 10**9
    indmin = -1
    for i in range(N):
        if A[i]<0:
            Ind.append(i)
            if A[i]<amin:
                amin = A[i]
                indmin = i
    if len(Ind)==0:
        print(sum(A))
    else:
        B = [0]*(N+1)
        for i in range(1,N+1):
            B[i] = B[i-1]+A[i]
        lmin = 10**9
        indl = -1
        rmin = 10**9
        indr = -1
        for i in Ind:
            if i<indmin:
                if B[indmin-1]-B[i-1]<lmin:
                    lmin = B[indmin-1]-B[i-1]
                    indl = i
            elif i>indmin:
                if B[i]-B[indmin]<rmin:
                    rmin = B[i]-B[indmin]
                    indr = i
        ans = 0
        if lmin<0:
            ans += abs(B[indl-1])+abs(lmin)
        else:
            ans += abs(B[indmin-1])
        if rmin<0:
            ans += abs(B[N]-B[indr])+abs(rmin)
        else:
            ans += abs(B[N]-B[indmin])
        ans += abs(amin)
        print(ans)