for _ in range(int(input())):
n = int(input())
arr = list(map(int, input().split()))
l = [0] * n
r = [0] * n
l[0] = arr[0]
r[-1] = arr[-1]
for i in range(1, n):
l[i] = max(l[i - 1], arr[i])
r[n - i - 1] = max(r[n - i], arr[n - i - 1])
s = 0
for i in range(n):
s += min(l[i], r[i])
print(s)
1650A - Deletions of Two Adjacent Letters | 1512A - Spy Detected |
282A - Bit++ | 69A - Young Physicist |
1651A - Playoff | 734A - Anton and Danik |
1300B - Assigning to Classes | 1647A - Madoka and Math Dad |
710A - King Moves | 1131A - Sea Battle |
118A - String Task | 236A - Boy or Girl |
271A - Beautiful Year | 520B - Two Buttons |
231A - Team | 479C - Exams |
1030A - In Search of an Easy Problem | 158A - Next Round |
71A - Way Too Long Words | 160A - Twins |
1A - Theatre Square | 1614B - Divan and a New Project |
791A - Bear and Big Brother | 1452A - Robot Program |
344A - Magnets | 96A - Football |
702B - Powers of Two | 1036A - Function Height |
443A - Anton and Letters | 1478B - Nezzar and Lucky Number |