#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long
#define ar array
#define pii pair<int, int>
#define sz(s) (int) s.size()
#define all(s) s.begin(), s.end()
template<class T> bool uin(T &a, T b) { return a > b ? (a = b, true) : false; }
template<class T> bool uax(T &a, T b) { return a < b ? (a = b, true) : false; }
const int N = 2e5 + 5;
struct BIT {
int t[N];
void upd(int x, int v) {
for (int i = x; i < N; i += i & (-i)) t[i] += v;
}
int qry(int x) {
int ret = 0;
for (int i = x; i > 0; i -= i & (-i)) ret += t[i];
return ret;
}
} bit;
vector<pii> ord[N];
ll count_swaps(std::vector<int> s) {
int n = sz(s) / 2;
ll ret = 0;
vector<pii> v;
for (int i = 0; i < sz(s); i++) {
ord[abs(s[i])].emplace_back(s[i], i);
}
for (int i = 1; i <= n; i++) {
sort(all(ord[i]));
for (int j = 0; j < sz(ord[i]) / 2; j++) {
int l = ord[i][j].second;
int r = ord[i][j + sz(ord[i]) / 2].second;
if (l > r) {
swap(l, r);
ret++;
}
v.emplace_back(l + 1, r + 1);
}
}
for (int i = 1; i <= 2 * n; i++) bit.upd(i, 1);
sort(all(v));
for (auto i : v) {
ret += bit.qry(i.second - 1) - bit.qry(i.first);
bit.upd(i.first, -1);
bit.upd(i.second, -1);
}
return ret;
}
