#include <bits/stdc++.h>   using namespace std;   void swap(int &a, int &b) {     int temp;     temp = a;     a = b;     b = temp;   }   void printarr(int a[], int n) {     for (int i = 0; i < 2 * n; i++) cout << a[i] <<    ;     cout << endl;   }   int main() {     long long int n, k, v;     cin >> n;     int a[2 * n], i, j, count = 0;     for (i = 0; i < 2 * n; i++) cin >> a[i];     for (i = 0; i < 2 * n; i += 2) {       if (a[i] != a[i + 1]) {         j = a[i];         for (k = i + 1; k < 2 * n; k++) {           if (j == a[k]) {             v = k;             while (v > i + 1) {               count++;               swap(a[v], a[v - 1]);               v--;             }           }         }       }     }     cout << count;     return 0;   }   