N = int(input())
*A, = map(int, input().split())
*X, = map(int, input().split())
*Y, = map(int, input().split())

X0 = sorted(set(A))
Z = {e: i for i, e in enumerate(X0)}
N1 = len(X0)

N0 = 2**(N1-1).bit_length()
X0 = X0 + [10**6] * (N0 - N1)
data = [None]*(2*N0+1)

def f(line, x):
    p, q = line
    return p*x + q

def _add_line(line, k, l, r):
    m = (l + r) // 2
    if data[k] is None:
        data[k] = line
        return
    lx = X0[l]
    mx = X0[m]
    rx = X0[r-1]
    left = (f(line, lx) < f(data[k], lx))
    mid = (f(line, mx) < f(data[k], mx))
    right = (f(line, rx) < f(data[k], rx))
    if left and right:
        data[k] = line
        return
    if not left and not right:
        return
    if mid:
        data[k], line = line, data[k]
    if left != mid:
        _add_line(line, 2*k+1, l, m)
    else:
        _add_line(line, 2*k+2, m, r)

def add_line(line, a, b):
    L = a + N0; R = b + N0
    a0 = a; b0 = b
    sz = 1
    while L < R:
        if R & 1:
            R -= 1
            b0 -= sz
            _add_line(line, R-1, b0, b0+sz)
        if L & 1:
            _add_line(line, L-1, a0, a0+sz)
            L += 1
            a0 += sz
        L >>= 1; R >>= 1
        sz <<= 1

def query(k):
    x = X0[k]
    def gen(k, x):
        k += N0-1
        while k >= 0:
            if data[k]:
                yield f(data[k], x)
            k = (k - 1) // 2
    return min(gen(k, x))

v = 0
j = -1
for i in range(N):
    x = X[i]; a = A[i]; y = Y[i]
    while j+1 < N1 and X0[j+1] < x:
        j += 1
    add_line((-1, x+y+v), 0, j+1)
    add_line((1, -x+y+v), j+1, N0)
    v = query(Z[a])
print(v)