N = int(input())
A = [list(map(int, input().split())) for _ in range(3)]

# dp[i][j][k] := i個目まで決めて、i個目はj回焼いている、変化がk回起きた
dp = [[[0]*5 for _ in range(3)] for _ in range(N+1)]
for i in range(N):
    for j in range(3):
        for k in range(5):
            # そこで終わる
            if j-1 >= 0 and k+1 < 5:
                dp[i+1][j-1][k+1] = max(dp[i+1][j-1][k+1], dp[i][j][k] + A[j-1][i])
            # 継続
            dp[i+1][j][k] = max(dp[i+1][j][k], dp[i][j][k] + A[j][i])

            # そこから焼く
            if j+1 < 3 and k+1 < 5:
                dp[i+1][j+1][k+1] = max(dp[i+1][j+1][k+1], dp[i][j][k] + A[j+1][i])

ans = 0
for j in range(3):
    for k in range(5):
        ans = max(ans, dp[N][j][k])
print(ans)