T = int(input())
DIV = 10 ** 9 + 7
for _ in range(T):
    N = int(input())
    A = list(map(int,input().split()))
    while len(A) >= 2:
        x = A.pop()
        y = A.pop()
        A.append((x + 1) * (y + 1) - 1)
    print(A[0])