n = int(input())
A = list(map(int, input().split()))
B = list(map(int, input().split()))
X = list(map(int, input().split()))
Y = list(map(int, input().split()))

total = 0
for i in range(n):
    a = 2 * i
    b = 2 * i + 1
    same_a = A[a] + A[b]
    same_b = B[a] + B[b]
    same = max(same_a, same_b) + X[i]
    diff1 = A[a] + B[b]
    diff2 = B[a] + A[b]
    diff = max(diff1, diff2) + Y[i]
    total += max(same, diff)
print(total)