#include <iostream>
#include <vector>

using namespace std ;

/*ifstream cin ("input") ;
ofstream cout ("output") ;*/

class FenwickTree
{
public:
	FenwickTree(int n){
		this -> n = n ;
		aib.resize (n + 1) ;
	}
	void Update (int pos, int value) {
		update (pos, value) ;
	}
	int Query (int a, int b) {
		return query (b) - query (a - 1);
	}
private:
	int n ;
	vector <int> aib ;
	int lsb (int x) {
		return x & -x ;
	}	
	void update (int pos, int value) {
		for (; pos <= n; pos += lsb (pos)) {
			aib [pos] += value ;
		}
	}
	int query (int pos) {
		int s = 0 ;
		while (pos) {
			s += aib [pos] ;
			pos -= lsb (pos) ;
		}
		return s ;
	}
};

int main(int argc, char const *argv[])
{
	int n ;
	cin >> n ;
	FenwickTree *F = new FenwickTree (2 * n) ;
	vector <int> last (n + 1, 0) ;
	long long solution = 0 ;
	for (int i = 1 ; i <= 2 * n ; ++ i) {
		int x ;
		cin >> x ; /*cout << x << '\n' ;*/
		if (last [x] == 0) {
			F -> Update (i, 1) ;
			last [x] = i;
		}
		else {
			solution += 1LL * F -> Query (last[x] + 1, i) ;
			//cout << "am adunat " << 1LL * F -> Query (last[x], i) << " pentru " << x << '\n' ;
			F -> Update (last[x], -1) ;
		}
	}
	cout << solution << '\n' ;
	return 0;
}