#include <bits/stdc++.h>
typedef long long LL;
typedef unsigned long long ULL;
using namespace std;
int caseno = 1;
template <class T>
bool Inside(T a, T b, T c) {
  return a <= b && b <= c;
}
template <class T>
inline void SWAP(T &a, T &b) {
  T t = a;
  a = b;
  b = t;
}
inline LL POW(LL base, LL power) {
  LL res = base;
  if (power == 0) return 1;
  for (int I = 0; I < power - 1; I++) res *= base;
  return res;
}
int ToInt(string s) {
  int r = 0;
  istringstream sin(s);
  sin >> r;
  return r;
}
double ToDouble(string s) {
  double r = 0;
  istringstream sin(s);
  sin >> r;
  return r;
}
string ToString(int n) {
  string s;
  stringstream convert;
  convert << n;
  s = convert.str();
  return s;
}
const int SIZE = 1e6;
vector<int> v;
int main() {
  std::ios_base::sync_with_stdio(0);
  int T, I, J, K, N, n, m, k, len, x;
  cin >> n;
  for (I = 0; I < 2 * n; I++) {
    cin >> x;
    v.push_back(x);
  }
  LL cnt = 0;
  for (I = 0; I < 2 * n; I++) {
    if (v[I + 1] == v[I]) continue;
    for (J = I + 1; J < 2 * n; J++) {
      if (v[J] == v[I]) {
        v.erase(v.begin() + J);
        v.insert(v.begin() + I, v[I]);
        cnt += (J - I - 1);
        break;
      }
    }
  }
  cout << cnt << '\n';
  return 0;
}
