#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define ff first
#define ss second
#define _ << " " <<
#define yes cout<<"YES\n"
#define no cout<<"NO\n"
#define ull unsigned long long
#define lll __int128
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define BlueCrowner ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define FOR(i, a, b) for (ll i = (a); i < (b); i++)
#define FORD(i, a, b) for (ll i = (a); i >= (b); i--)
const ll mod = 1e9 + 7;
const ll mod1 = 998244353;
const ll naim = 1e9;
const ll max_bit = 60;
const ull tom = ULLONG_MAX;
const ll MAXN = 100005;
const ll LOG = 20;
const ll NAIM = 1e18;
const ll N = 2e6 + 5;
// ---------- GCD ----------
ll gcd(ll a, ll b) {
while (b) {
a %= b;
swap(a, b);
}
return a;
}
// ---------- LCM ----------
ll lcm(ll a, ll b) {
return a / gcd(a, b) * b;
}
// ---------- Modular Exponentiation ----------
ll modpow(ll a, ll b, ll m = mod) {
ll c = 1;
a %= m;
while (b > 0) {
if (b & 1) c = c * a % m;
a = a * a % m;
b >>= 1;
}
return c;
}
// ---------- Modular Inverse (Fermat’s Little Theorem) ----------
ll modinv(ll a, ll m = mod) {
return modpow(a, m - 2, m);
}
// ---------- Factorials and Inverse Factorials ----------
ll fact[N], invfact[N];
void pre_fact(ll n = N-1, ll m = mod) {
fact[0] = 1;
for (ll i = 1; i <= n; i++) fact[i] = fact[i-1] * i % m;
invfact[n] = modinv(fact[n], m);
for (ll i = n; i > 0; i--) invfact[i-1] = invfact[i] * i % m;
}
// ---------- nCr ----------
ll nCr(ll n, ll r, ll m = mod) {
if (r < 0 || r > n) return 0;
return fact[n] * invfact[r] % m * invfact[n-r] % m;
}
// ---------- Sieve of Eratosthenes ----------
vector<ll> primes;
bool is_prime[N];
void sieve(ll n = N-1) {
fill(is_prime, is_prime + n + 1, true);
is_prime[0] = is_prime[1] = false;
for (ll i = 2; i * i <= n; i++) {
if (is_prime[i]) {
for (ll j = i * i; j <= n; j += i)
is_prime[j] = false;
}
}
for (ll i = 2; i <= n; i++)
if (is_prime[i]) primes.pb(i);
}
//2 + 7 + 1 + 3 + 9
ll count_swaps(vector<int> S){
ll n = S.size() / 2;
set<ll> nums;
for(auto &x : S) nums.insert(abs(x));
vector<queue<ll>> posL(n + 1);
vector<queue<ll>> posR(n + 1);
FOR(i, 0, 2 * n){
if(S[i] < 0) posL[-S[i]].push(i);
else posR[S[i]].push(i);
}
struct BIT{
ll n;
vector<ll> sum;
BIT(ll _n){
n = _n;
sum.assign(n + 1, 0ll);
}
void add(ll pos, ll val){
for(ll i = pos; i <= n; i += i & -i) sum[i] += val;
}
void update(ll l, ll r, ll val){
add(l, val);
add(r + 1, -val);
}
ll query(ll pos){
ll ans = 0;
for(ll i = pos; i > 0; i -= i & -i) ans += sum[i];
return ans;
}
};
BIT bit(2 * n);
ll ans = 0;
vector<bool> used(2 * n, 0);
FOR(i, 0, n * 2){
ll x = abs(S[i]);
if(posL[x].empty()) continue;
ll topL = posL[x].front();
ll topR = posR[x].front();
if(used[min(topL, topR)]) continue;
vector<pair<ll, ll>> ranges;
posL[x].pop();
posR[x].pop();
used[topL] = 1;
used[topR] = 1;
if(topL > topR) {
ans += topL - topR + bit.query(topL + 1) - bit.query(topR + 1);
ranges.pb({topR + 1, topL});
}
else {
ans += topR - topL - 1 + bit.query(topR + 1) - bit.query(topL + 1);
ranges.pb({topL + 2, topR});
}
for(auto &x : ranges) bit.update(x.ff, x.ss, 1);
}
return ans;
// 3 + 2 + 1 + 7 + 11
// 9 + 7 + 5 + 2 + 1 + 1
}
/*void solve() {
ll n; cin >> n;
vector<int> S(n * 2);
for(auto &x : S) cin >> x;
cout << count_swaps(S) << '\n';
}
int main() {
BlueCrowner;
ll t = 1;
//cin >> t;
while (t--) {
solve();
}
return 0;
}*/
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