#include "bits/stdc++.h"
using namespace std;
typedef long long int ll;
ll countMerge(vector<int>& arr, int l, int m, int r){
int n1 = m-l+1;
int n2 = r-m;
vector<int> left(n1);
vector<int> right(n2);
for(int i = 0; i < n1; i++) left[i] = arr[i+l];
for(int i = 0; i < n2; i++) right[i] = arr[m + 1 + i];
ll res = 0;
int i = 0, j = 0, k = l;
while (i < n1 && j < n2) {
if (left[i] <= right[j]) arr[k++] = left[i++];
else {
arr[k++] = right[j++];
res += (n1 - i);
}
}
while (i < n1) arr[k++] = left[i++];
while (j < n2) arr[k++] = right[j++];
return res;
}
ll countInv(vector<int>& arr, int l, int r){
ll res = 0;
if (l < r) {
int m = (r + l) / 2;
res += countInv(arr, l, m);
res += countInv(arr, m + 1, r);
res += countMerge(arr, l, m, r);
}
return res;
}
ll count_swaps(vector<int> S){
int n = S.size() / 2;
if(n == 1){
if(S[0] < 0) return 0;
return 1;
}
int neg = 0;
unordered_map<int, deque<int>> qs;
unordered_map<int, deque<int>> ps;
unordered_map<int, int> counts;
vector<int> poop(n*2);
for(int i = 0; i < n*2; i++){
int oldCount = counts[abs(S[i])];
counts[abs(S[i])] += S[i]/abs(S[i]);
if(abs(oldCount) > abs(counts[S[i]])){
qs[abs(S[i])].push_back(neg);
ps[abs(S[i])].push_back(neg+1);
neg += 2;
}
}
// for(auto [a, aa] : qs){
// cerr << a << ": ";
// for (int b : aa) {
// cerr << b << " ";
// }
// cerr << '\n';
// }
for(int i = 0; i < n*2; i++){
if(S[i] < 0){
poop[i] = qs[abs(S[i])].front(); qs[abs(S[i])].pop_front();
}
else{
poop[i] = ps[S[i]].front(); ps[S[i]].pop_front();
}
}
// for(int i = 0; i < n*2; i++){
// cerr << poop[i] << ' ';
// }
// cerr << '\n';
return countInv(poop, 0, n*2-1);
}
// int main(){
// cout << "Poop\n";
// cout << count_swaps({2, -1, -2, 1});
// return 0;
// }
