#include <iostream>
using namespace std;

int main()
{
    int n, counter = 0;
    cin >> n;
    int arr[n * 2];
    int len = sizeof(arr) / sizeof(arr[0]);
    for (int i = 0; i < len; i++)
    {
        cin >> arr[i];
    }
    for (int i = 0; i < len; i++)
    {
        for (int j = i + 1; j <= len; j++)
        {
            if (arr[j] == arr[i])
            {
                counter += j - i;
                break;
            }
        }
    }
    cout << counter;

    return 0;
}