#include <bits/stdc++.h>
// mrrrow meeow :3
// go play vivid/stasis now! it's free on steam
#define fo(i, a, b) for (auto i = (a); i < (b); i++)
#define of(i, a, b) for (auto i = (b); i-- > (a);)
#define f first
#define s second
#define pb push_back
#define pob pop_back
#define lb lower_bound
#define ub upper_bound
#define be(a) a.begin(), a.end()
using namespace std;
int ____init = [] {
ios::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
return 0;
}();
int bit[200001];
void add(int i, int v) {
for (i++; i <= 200000; i += i & -i) bit[i] += v;
}
int get(int i) {
int res = 0;
for (i++; i > 0; i -= i & -i) res += bit[i];
return res;
}
long long count_swaps(vector<int> s) {
long long n = s.size() / 2;
map<int, set<int>> m;
fo(i, 0, 2 * n) {
m[s[i]].insert(i);
add(i, 1);
}
add(0, -1);
long long res = 0;
int zero = 0;
fo(i, 0, n) {
while (get(zero) != 0) zero++;
int first_curr = zero;
int first_other = *m[-s[first_curr]].begin();
m[s[first_curr]].erase(first_curr);
m[s[first_other]].erase(first_other);
if (s[first_curr] > 0) swap(first_curr, first_other);
cerr << s[first_curr] << ' ' << s[first_other] << endl;
res += get(first_curr);
add(first_curr, -1);
res += get(first_other);
add(first_other, -1);
}
return res;
}
