### BUGGY CODE ###

# Binary Indexed Tree (Fenwick Tree)
class BIT():
    """一点加算、区間取得クエリをそれぞれO(logN)で答える
    add: i番目にvalを加える
    get_sum: 区間[l, r)の和を求める
    i, l, rは0-indexed
    """
    def __init__(self, n):
        self.n = n
        self.bit = [0] * (n + 1)

    def _sum(self, i):
        s = 0
        while i > 0:
            s += self.bit[i]
            i -= i & -i
        return s

    def add(self, i, val):
        """i番目にvalを加える"""
        i = i + 1
        while i <= self.n:
            self.bit[i] += val
            i += i & -i

    def get_sum(self, l, r):
        """区間[l, r)の和を求める"""
        return self._sum(r) - self._sum(l)


from operator import itemgetter

n = int(input())
a = list(map(int, input().split()))
b = list(map(int, input().split()))
ans = 10**18

for bit_state in range(1 << n):
    tmp = [0] * n
    pos_even_palok = set()
    pos_odd_palok = set()
    pos_even_palng = set()
    pos_odd_palng = set()
    pattern = [[] for i in range(2)]

    for i in range(n):
        if bit_state & (1 << i) and i % 2 == 0:
            pattern[0].append((a[i], i))
            tmp[i] = 0
        elif bit_state & (1 << i) and i % 2 == 1:
            pattern[1].append((a[i], i))
            tmp[i] = 1
        elif i % 2 == 0:
            pattern[1].append((b[i], i))
            tmp[i] = 1
        else:
            pattern[0].append((b[i], i))
            tmp[i] = 0
     
    for i in range(2):
        pattern[i] = sorted(pattern[i], key = itemgetter(1))
        pattern[i] = sorted(pattern[i])
    if len(pattern[0]) == len(pattern[1]) or len(pattern[0]) - 1 == len(pattern[1]):
        bit = BIT(n)
        ans_tmp = 0
        prev_num = 10**8
        for i in range(n)[::-1]:
            pal = i % 2
            num, ind = pattern[pal][-1]
            if prev_num < num:
                break
            prev_num = num
            del(pattern[pal][-1])
            bit.add(ind, 1)
            ans_tmp += bit.get_sum(0, ind)
        else:
            ans = min(ans, ans_tmp)

if ans == 10**18:
    print(-1)
else:
    print(ans)


### FIXED CODE ###

# Binary Indexed Tree (Fenwick Tree)
class BIT():
    """一点加算、区間取得クエリをそれぞれO(logN)で答える
    add: i番目にvalを加える
    get_sum: 区間[l, r)の和を求める
    i, l, rは0-indexed
    """
    def __init__(self, n):
        self.n = n
        self.bit = [0] * (n + 1)

    def _sum(self, i):
        s = 0
        while i > 0:
            s += self.bit[i]
            i -= i & -i
        return s

    def add(self, i, val):
        """i番目にvalを加える"""
        i = i + 1
        while i <= self.n:
            self.bit[i] += val
            i += i & -i

    def get_sum(self, l, r):
        """区間[l, r)の和を求める"""
        return self._sum(r) - self._sum(l)


from operator import itemgetter
from collections import deque

n = int(input())
a = list(map(int, input().split()))
b = list(map(int, input().split()))
ans = 10**18


for bit_state in range(1 << n):
    pattern = [[] for i in range(2)]
    for i in range(n):
        if bit_state & (1 << i) and i % 2 == 0:
            pattern[0].append(a[i]*100 + i)
        elif bit_state & (1 << i) and i % 2 == 1:
            pattern[1].append(a[i]*100 + i)
        elif i % 2 == 0:
            pattern[1].append(b[i]*100 + i)
        else:
            pattern[0].append(b[i]*100 + i)

    if len(pattern[0]) == len(pattern[1]) or len(pattern[0]) - 1 == len(pattern[1]):
        for i in range(2):
            pattern[i] = sorted(pattern[i])
        bit = BIT(n)
        ans_tmp = 0
        prev_num = 10**8
        for i in range(n)[::-1]:
            pal = i % 2
            num = pattern[pal].pop()
            ind = num % 100
            num = num // 100
            if prev_num < num:
                break
            prev_num = num
            bit.add(ind, 1)
            ans_tmp += bit.get_sum(0, ind)
        else:
            ans = min(ans, ans_tmp)

if ans == 10**18:
    print(-1)
else:
    print(ans)