#include <bits/stdc++.h>
using namespace std;
const int N = 106, INF = 0x3f3f3f3f;
int read() {
  int x = 0, f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    x = x * 10 + ch - '0';
    ch = getchar();
  }
  return x * f;
}
int n, a[N << 1];
int couple[N][2];
int main() {
  n = read();
  for (int i = 1; i <= n << 1; i++) {
    a[i] = read();
    if (!couple[a[i]][0])
      couple[a[i]][0] = i;
    else
      couple[a[i]][1] = i;
  }
  int ans = 0;
  for (int i = 1; i <= (n << 1); i += 2) {
    if (a[i] == a[i + 1])
      continue;
    else {
      ans += couple[a[i]][1] - couple[a[i]][0] - 1;
      for (int j = couple[a[i]][1] - 1; j >= i; j--)
        if (couple[a[j]][0] == j)
          a[++couple[a[j]][0]] = a[j];
        else
          a[++couple[a[j]][1]] = a[j];
      a[couple[a[i]][1] = i + 1] = a[i];
    }
  }
  printf("%d\n", ans);
}
