#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pullull;
typedef pair<ll, int> plli;
typedef pair<int, pii> pipii;
typedef vector<vector<int> > mati;
typedef vector<vector<double> > matd;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;
typedef vector<vector<vector<ll>>> vvvll;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
typedef vector<vector<vector<bool>>> vvvb;
typedef vector<pll> vpll;
typedef vector<vpll> vvpll;

#define FOR(i,x,y) for(ll i=(ll)x; i<(ll)y; ++i)
#define REP(i,y) FOR(i, 0, y)
#define RFOR(i,x,y) for(ll i=(ll)x; i>=(ll)y; --i)
#define RREP(i,x) RFOR(i, x, 0)
#define ALL(a) a.begin(), a.end()
#define pb push_back

inline void IN(void){
  return;
}

template <typename First, typename... Rest>
void IN(First& first, Rest&... rest){
  cin >> first;
  IN(rest...);
  return;
}

inline void OUT(void){
  cout << "\n";
  return;
}

template <typename First, typename... Rest>
void OUT(First first, Rest... rest){
  cout << first << " ";
  OUT(rest...);
  return;
}

template <typename T>
void vec_print(vector<T> VEC){
  REP(i, VEC.size()){
    cout << VEC[i] << " ";
  }
  cout << "\n";
};

template <typename T>
void mat_print(vector<vector<T> > MAT){
  REP(i, MAT.size()){
    REP(j, MAT[i].size()){
      cout << MAT[i][j] << " ";
    }
    cout << "\n";
  }
};

template <typename CLASS1, typename CLASS2>
class HOGE{
  public:
    CLASS1 key;
    CLASS2 value;
    HOGE(void){
      return;
    };
    HOGE(CLASS1 key, CLASS2 value){
      this->key = key;
      this->value = value;
    };
    ~HOGE(void){
      return;
    };

    void print(void){
      cout << "key : " << key << ", value : " << value << "\n";
      return;
    };
    
    bool operator==(const HOGE &obj){
      return (this->value == obj.value);
    };
    bool operator<(const HOGE &obj){
      return (this->value < obj.value);
    };
    bool operator>(const HOGE &obj){
      return (this->value > obj.value);
    };
};

template <typename CLASS1, typename CLASS2>
bool operator==(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value == hoge2.value;
};

template <typename CLASS1, typename CLASS2>
bool operator<(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value < hoge2.value;
};

template <typename CLASS1, typename CLASS2>
bool operator>(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value > hoge2.value;
};

constexpr int INF = (1<<30);
constexpr ll INFLL = 1LL<<62;
constexpr long double EPS = 1e-12;
constexpr ll MOD = (ll)((1E+9)+7);

ll N;
vvll X;
vll V_copy;
vll V;
vll Vb;

ll search(ll flag){
  ll flag_copy = flag;
  ll tmp1 = 0;
  REP(i,N){
    V[i] = X[i][flag_copy%2];
    V_copy[i] = V[i];
    tmp1 += flag_copy%2;
    Vb[i] = flag_copy%2;
    flag_copy>>=1;
  }
  if(tmp1%2==1) return INFLL;
  sort(ALL(V));
  vb touch(N, false);
  ll ans = 0;
  REP(i,N){
    bool flag_tmp = false;
    REP(j,N){
      if(touch[j]) continue;
      if(V[i]==V_copy[j] && (abs(i-j))%2==Vb[j]){
        flag_tmp = true;
        ans += abs(i-j);
        for(ll k=j-1; k>=i; --k){
          V_copy[k+1] = V_copy[k];
          Vb[k+1] = Vb[k]+1;
          Vb[k+1]%=2;
        }
        V_copy[i] = V[i];
        Vb[i] = 0;
        touch[i] = true;
        break;
      }
    }

    /*
    if(flag==10){
      vec_print(V_copy);
      vec_print(Vb);
      cout << endl;
    }
    */
    if(!flag_tmp){
      /*
      vec_print(touch);
      vec_print(Vb);
      vec_print(V_copy);
      */
      return INFLL;
    }
  }
  //fprintf(stderr, "%lld\n", flag);
  return ans;
}

int main(){
  cin.tie(0); // cut the cin and cout (default, std::flush is performed after std::cin)
  ios::sync_with_stdio(false); // cut the iostream and stdio (DON'T endl; BUT "\n";)

  IN(N);
  X.resize(N);
  REP(i,N) X[i].resize(2);
  V.resize(N);
  V_copy.resize(N);
  Vb.resize(N);
  REP(i,N) IN(X[i][0]);
  REP(i,N) IN(X[i][1]);

  ll ans=INFLL;

  REP(i,1<<N){
    ans = min(ans, search(i));
  }

  if(ans==INFLL){
    OUT(-1);
  }else{
    OUT(ans);
  }

  return 0;
}


Measured memory_bytes: 256