using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using static System.Console;
using static System.Math;
using static MyIO;
using static MyUtil;

public class D { public static void Main() => (new Solver()).Solve(); }

public class Solver
{
	public void Solve()
	{
		long N = GetLong();
		var A = GetLongs(N);
		var B = GetLongs(N);

		long INF = long.MaxValue / 2;
		long MASK = leftShift(1, N);
		var dp = new long[MASK, 64];
		for(long i = 0; i < MASK; i++)
		{
			for(long j = 0; j < 64; j++)
				dp[i, j] = INF;
		}
		dp[0, 0] = 0;
		for(long s = 0; s < MASK; s++)
		{
			long popcnt = 0;
			for(long i = 0; i < N; i++)
			{
				if(contains(s, i))
					popcnt++;
			}

			var cand = new List<(long, long)>();
			long head = popcnt;
			for(long i = 0; i < N; i++)
			{
				if(!contains(s, i))
				{
					cand.Add((i, head));
					head++;
				}
			}

			for(long i = 0; i < 64; i++)
			{
				if(dp[s, i] == INF)
					continue;

				foreach(var p in cand)
				{
					long idx = p.Item1;
					long pos = p.Item2;
					long j = Abs(idx - popcnt) % 2 == 0 ? A[idx] : B[idx];
					if(j >= i)
						chmin(ref dp[s | leftShift(1, idx), j], dp[s, i] + Abs(pos - popcnt));
				}
			}
		}

		long ans = INF;
		for(long i = 0; i < 64; i++)
			chmin(ref ans, dp[MASK - 1, i]);

		WriteLine((ans == INF) ? -1 : ans);
	}
}

public static class MyIO
{
	private static string[] args = new string[0];
	private static int cnt = 0;
	private static IEnumerable<string> getArgs(long N) => Range(0, N).Select(_ => getArg());
	private static string getArg()
	{
		if(cnt == args.Length) { args = Console.ReadLine().Split(); cnt = 0; }
		return args[cnt++];
	}

	public static int GetInt() => int.Parse(getArg());
	public static long GetLong() => long.Parse(getArg());
	public static double GetDouble() => double.Parse(getArg());
	public static decimal GetDecimal() => decimal.Parse(getArg());
	public static string GetString() => getArg();
	public static char GetChar() => getArg()[0];
	public static int[] GetInts(long N) => getArgs(N).Select(int.Parse).ToArray();
	public static long[] GetLongs(long N) => getArgs(N).Select(long.Parse).ToArray();
	public static double[] GetDoubles(long N) => getArgs(N).Select(double.Parse).ToArray();
	public static decimal[] GetDecimals(long N) => getArgs(N).Select(decimal.Parse).ToArray();
	public static string[] GetStrings(long N) => getArgs(N).ToArray();
}

public static class MyUtil
{
	public static void chmax<T>(ref T x, T y) where T : IComparable<T> { if(x.CompareTo(y) < 0) x = y; }
	public static void chmin<T>(ref T x, T y) where T : IComparable<T> { if(x.CompareTo(y) > 0)	x = y; }
	public static void swap<T>(ref T x, ref T y) { T tmp = x; x = y; y = tmp; }
	public static long rightShift(long x, long y) => (x >> (int)y);
	public static long leftShift(long x, long y) => (x << (int)y);
	public static bool contains(long s, long x) => (rightShift(s, x) & 1L) == 1L;
	public static long gcd(long x, long y) => (y == 0) ? x : gcd(y, x % y);
	public static long lcm(long x, long y) => (x / gcd(x,y)) * y;	
	public static IEnumerable<int> Range(long start, long count) => Enumerable.Range((int)start, (int)count);
	public static void Sort(this List<string> source) => source.Sort(StringComparer.Ordinal);
}


Measured memory_bytes: 178336