INF = 10 ** 18
for _ in range(int(input())):
    n = int(input())
    dp0p = dp0n = 0
    dp1p = dp1n = dp2p = dp2n = -INF
    for x in map(int, input().split()):
        dp2p = max(dp2p, dp1n) + x
        dp2n = max(dp2n, dp1p) - x
        dp1p = max(dp1p, dp0n) + x
        dp1n = max(dp1n, dp0p) - x
        dp0p += x
        dp0n -= x
    print(max(dp0p, dp0n, dp1p, dp1n, dp2p, dp2n))