#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma")
#pragma GCC optimize("unroll-loops")
using namespace std;
long long MOD = 998244353;
double eps = 1e-12;
void solve() {
  int n;
  cin >> n;
  n *= 2;
  int a[n];
  bool done[n + 10];
  memset(done, 0, sizeof(done));
  int i;
  for (long long i = 0; i < n; i++) {
    cin >> a[i];
  }
  int ans = 0;
  for (int i = 0; i < n; i++) {
    if (done[a[i]]) continue;
    if (a[i] != a[i + 1]) {
      done[a[i]] = 1;
      int j;
      for (int z = n - 1; z > i; z--)
        if (a[z] == a[i]) {
          j = z;
          break;
        }
      for (j; j - i > 1 && a[i] != a[i + 1]; j--) {
        swap(a[j], a[j - 1]);
        ans++;
      }
    }
    done[a[i]] = 1;
  }
  cout << ans;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  solve();
  return 0;
}
