#include <cstdio>
#include <algorithm>

using namespace std;

int ap[50010], aib[100010];

void update (int poz, int val)
{
    for (; poz <= 100005; poz += (poz & (-poz)))
        aib[poz] += val;
}

int query (int poz)
{
    int rez = 0;
    for (; poz > 0; poz -= (poz & (-poz)))
        rez += aib[poz];

    return rez;
}

int main ()
{
   // freopen ("cc.in", "r", stdin);

    int n;
    scanf ("%d", &n);

    long long nr = 0LL;
    for (int i = 1; i <= 2 * n; ++i)
    {
        int x;
        scanf ("%d", &x);

        if (!ap[x]) update (i, 1);
        else
        {
            nr += 1LL * (query (i) - query (ap[x]));
            update (ap[x], -1);
        }

        ap[x] = i;
    }

    printf ("%lld\n", nr);

    return 0;
}