def check(a)
  a.uniq.size == 3 && (a.max == a[1] || a.min == a[1])
end

def func(n, a)
  dp = [0i64] * -~n
  (0..n).each do |i|
    dp[i] = {dp[i], dp[i - 1] || 0i64}.max
    dp[i + 3] = {dp[i + 3], dp[i] + a[i]}.max if check(a[i, 3])
  end
  dp[n]
end

read_line.to_i.times do
  n = read_line.to_i
  a = read_line.split.map(&.to_i64)
  puts [func(n, a), func(n, a[1..] + a[0, 1]), func(n, a[2..] + a[0, 2])].max
end