import sequtils,strutils,math
type
    priorityQue[I:static[int];T:tuple] = array[I + 1,T]
    item = tuple[cost: int,ID : int]
proc push[T](A:var priorityQue; b: T;)=
    const key = 0
    A[0][0] += 1
    A[A[0][0]] = b # A[0][0]はsize、最大のIndex
    var index = A[0][0]
    while index > 1 and A[index][key] > A[index div 2][key]:
        (A[index],A[index div 2]) = (A[index div 2],A[index])
        index = index div 2
proc pop(A: var priorityQue):item = #戻り値を書き換える
    const key = 0
    result = A[1]
    A[1] = A[A[0][0]]
    A[A[0][0]] = (0,0)
    A[0][0] -= 1
    var index = 1
    while index * 2 <= A[0][0]:
        if index * 2 + 1<= A[0][0]:
            if A[index][key] < A[index * 2][key] and A[index * 2 + 1][key] <= A[index * 2][key]:
                (A[index],A[index * 2]) = (A[index * 2],A[index])
                index = index * 2
            elif A[index][key] < A[index * 2 + 1][key]:
                (A[index],A[index * 2 + 1]) = (A[index * 2 + 1],A[index])
                index = index * 2 + 1
            else:
                break
        elif index * 2 <= A[0][0]:
            if A[index][key] < A[index * 2][key]:
                (A[index],A[index * 2]) = (A[index * 2],A[index])
            break
        else:
            break

proc size(A : priorityQue):int=
    return A[0][0]

var
    N = stdin.readline.parseInt
    A = stdin.readline.split.map(parseInt)
    B = stdin.readline.split.map(parseInt)
    pQueA : priorityQue[1500,item]
    p : int
    ans,cnt : int
    monster : item
for n in 0..<N:
    pQueA.push((- A[n] * 10000 ,n))
ans = high(int)
for n in 0..<N:
    var pQueB = pQueA
    for i in 0..<N:
        p = (n + i) mod N
        monster = pQueB.pop
        monster.cost -= 1
        monster.cost -= B[p] div 2 * 10000
        pQueB.push(monster)
    cnt = 0
    while pQueB.size > 0:
        monster = pQueB.pop
        cnt = max(cnt, (-1 * monster.cost) mod 10000)
    ans = min(ans,cnt)
echo ans