#include "vector"
#include "stdio.h"
#include "iostream"
using namespace std;
long long count_swaps(std::vector<int> s) {
vector<bool> used(s.size(), false);
long long cnt = 0;
// cout << "size:" << s.size() << "\n";
for (int i = 0; i < (int)s.size(); i++) {
int j;
if (used[i]) {
continue;
}
// cout << "to pair" << i << "\n";
int cnt_used = 0;
for (j = i + 1; j < (int)s.size(); j++) {
cnt_used += used[j];
if (s[j] == -s[i] and !used[j]) {
used[j] = true;
break;
}
}
if (j < (int)s.size()) {
// cout << i << ": " << s[i] << " , "<< j << ": " << s[j] << "\n";
long long distance = j - i - (s[i] < 0 ? 1 : 0) - cnt_used;
cnt += distance;
}
}
return cnt;
}
int mani() {
int n;
if (scanf("%d\n", &n));
vector<int> A(n << 1);
for (int i = 0; i < n << 1; i++) {
if (scanf("%d", &A[i]));
}
printf("%lld\n", count_swaps(A));
return 0;
}
