#include <bits/stdc++.h>
#define ericxiao cin.tie(0); ios_base::sync_with_stdio(false);
#define endl '\n'
// #define int long long
using namespace std;
typedef pair<int,int> pii;
const int maxn=1e5+10;
deque<int> posl[maxn],posr[maxn];
struct BIT{
int v[maxn],n;
int lb(int x){return x&(-x);}
void init(int x){n=x; for(int i=1;i<=n;i++) v[i]=lb(i);}
void modify(int x,int k){while(x<=n) v[x]+=k,x+=lb(x);}
int query(int x){int t=0; while(x>0) t+=v[x],x-=lb(x); return t;}
int get(int l,int r){return query(r+1)-query(l);}
void del(int x){modify(x+1,-1);}
void print(){for(int i=0;i<n;i++) cout<<get(i,i)<<' '; cout<<endl;}
} tree;
int count_swaps(vector<int> v){
int n=v.size(),ans=0; tree.init(n);
for(int i=0;i<n;i++){
if(v[i]>0) posr[v[i]].push_back(i);
else posl[-v[i]].push_back(i);
}
// tree.print();
for(int i=0;i<n/2;i++){
if(v[i]>0)
ans+=tree.get(0,posl[v[i]].front())-1;
else
ans+=tree.get(1,posr[-v[i]].front())-1;
tree.del(posl[abs(v[i])].front()); tree.del(posr[abs(v[i])].front());
posl[abs(v[i])].pop_front(); posr[abs(v[i])].pop_front();
// tree.print(); cout<<"ans: "<<ans<<endl;
}
return ans;
}
// signed main(){
// int n; cin>>n;
// vector<int> v(n);
// for(int i=0;i<n;i++) cin>>v[i];
// cout<<count_swaps(v)<<endl;
// return 0;
// }
