#include <algorithm>
#include <cassert>
#include <cfloat>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <deque>
#include <iostream>
#include <iterator>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

#define FOR(i,k,n) for(int(i)=(k);(i)<(n);++(i))
#define rep(i,n) FOR(i,0,n)
#define all(v) begin(v),end(v)
#define debug(x) std::cerr<<#x<<": "<<x<<"\n"
#define debug2(x,y) std::cerr<<#x<<": "<<x<<", "<<#y<<": "<<y<<"\n"
#define debug3(x,y,z) std::cerr<<#x<<": "<<x<<", "<<#y<<": "<<y<<", "<<#z<<": "<<z<<"\n"

using ll=long long;
using vi=std::vector<int>;
using vvi=std::vector<vi>;
using vll=std::vector<ll>;
using vvll=std::vector<vll>;
template<typename T> using vvec=std::vector<std::vector<T>>;
template<typename T>
auto make_v(size_t sz){return std::vector<T>(sz);}
template<typename T,typename... Ts>
auto make_v(size_t sz,Ts...ts){return std::vector<decltype(make_v<T>(ts...))>(sz,make_v<T>(ts...));}
template<typename T>
void fill_v(T&var,const T&x){var=x;}
template<typename V,typename T>
void fill_v(V&v,const T&x){for(auto&& w:v){fill_v(w,x);}}

template<typename T> std::ostream& operator<<(std::ostream&s,const std::vector<T>&v){
  int sz=v.size();s<<"\n";rep(i,sz){s<<v[i];if(i<sz-1){s<<"\t";}}s<<"\n";return s;}
template<typename T> std::ostream& operator<<(std::ostream&s,const std::vector<std::vector<T>>&v){
  for(auto&& w:v){s<<w;}return s;}
template<typename T> std::ostream& operator<<(std::ostream&s,const std::deque<T>&v){
  int sz=v.size();s<<"\n";rep(i,sz){s<<v[i];if(i<sz-1){s<<"\t";}}s<<"\n";return s;}
template<typename T> std::ostream& operator<<(std::ostream&s,const std::deque<std::deque<T>>&v){
  for(auto&& w:v){s<<w;}return s;}
template<typename T> std::ostream& operator<<(std::ostream&s, const std::set<T>&v){
  s<<"\n";for(auto&& elm:v){s<<elm<<"\t";}s<<"\n";return s;}

inline void scan(int&a){scanf("%d",&a);}
inline void scan(ll&a){scanf("%lld",&a);}
inline void scan(char&a){scanf(" %c",&a);}
inline void scan(double&a){scanf("%lf",&a);}
template<typename T>
inline void scan(std::vector<T>&v){for(auto&& sv:v){scan(sv);}}
template<typename First,typename...Args>
inline void scan(First&f,Args&...args){scan(f);scan(args...);}
inline void scan(std::string&s){char BUF[3000000];scanf(" %s",BUF);s=std::string(BUF);}
inline void print(int a){printf("%d\n",a);}
inline void print(ll a){printf("%lld\n",a);}
inline void print(double a){printf("%.12f\n",a);}
inline void print(std::string s){std::cout<<s<<"\n";}

using namespace std;

int n;
vvi merge(vvi& a, vvi& b) {
  assert ((int)a.size() == (n + 1) / 2);
  assert ((int)b.size() == n / 2);
  vvi ret(n);
  rep (i, n) {
    ret[i] = (i & 1) ? b[i/2] : a[i/2];
  }
  return ret;
}

bool sorted(vvi& a) {
  int sz = a.size();
  rep (i, sz-1) {
    if (a[i][0] > a[i+1][0]) {
      return false;
    }
  }
  return true;
}

// https://atcoder.jp/contests/chokudai_S001/submissions/1460844
ll merge_sort(vi &a) {
  int n = a.size();
  if (n == 1) {
    return 0;
  }
  ll ret = 0;
  vi b(begin(a), begin(a) + n/2);
  vi c(begin(a) + n/2, end(a));
  ret += merge_sort(b);
  ret += merge_sort(c);
  int sz_b = b.size();
  int sz_c = c.size();
  for (int i = 0, j = 0, k = 0; i < n; ++i) {
    if (j >= sz_b) {
      a[i] = c[k]; k += 1;
    } else if (k >= sz_c) {
      a[i] = b[j]; j += 1;
    } else if (b[j] <= c[k]) {
      a[i] = b[j]; j += 1;
    } else {
      a[i] = c[k]; k += 1;
      ret += n/2 - j;
    }
  }
  return ret;
}

int main() {
  scan(n);
  vi a(n), b(n);
  scan(a);
  scan(b);
  int m = (1 << n);
  ll ans = LLONG_MAX;
  rep (i, m) {
    if (__builtin_popcount(i) != n / 2) {
      continue;
    }
    vvi evens;
    vvi odds;
    rep (j, n) {
      bool odd = ((i >> j) & 1);
      if (odd) {
        if (j & 1) {
          odds.push_back({a[j], j});
        } else {
          odds.push_back({b[j], j});
        }
      } else {
        if (j & 1) {
          evens.push_back({b[j], j});
        } else {
          evens.push_back({a[j], j});
        }
      }
    }
    sort(all(evens));
    sort(all(odds));
    auto merged = merge(evens, odds);
    if (sorted(merged)) {
      vi idx(n);
      rep (i, n) {
        idx[i] = merged[i][1];
      }
      ll cans = merge_sort(idx);
      ans = min(ans, cans);
    }
  }
  if (ans == LLONG_MAX) {
    ans = -1;
  }
  print(ans);

  return 0;
}


Measured memory_bytes: 256