// Author: Kajetan Ramsza
#include "shoes.h"
#include "bits/stdc++.h"
using namespace std;
#define rep(i,a,b) for(int i=(a);i<(b);++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)x.size()
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef long long ll;
#ifdef DEBUG
auto& operator<<(auto& os, const pair<auto, auto> &p);
auto& operator<<(auto &os, const auto &v)
{ os<<"{"; for(auto it=begin(v);it!=end(v);++it) {
if(it != begin(v)) { os<<", "; } os<<(*it);
} return os<<"}"; }
auto& operator<<(auto &os, const pair<auto, auto> &p)
{ return os<<"("<<p.first<<", "<<p.second<<")"; }
void dbg_out(auto... x) { ((cerr<<' '<<x), ...) << endl; }
#define dbg(x...) cerr<<"("<<#x<<"):", dbg_out(x)
#else
#define dbg(...)
#endif
int n;
vi s;
vi edge;
vector<ll> num;
struct Tree {
static constexpr ll unit = 0;
vector<ll> s; int n;
Tree(int n_ = 0, ll def = unit) : s(2*n_, def), n(n_) {}
void update(int pos, ll val) {
for (s[pos += n] = val; pos /= 2;)
s[pos] = s[pos * 2] + s[pos * 2 + 1];
}
ll query(int b, int e) { // query [b, e)
ll res = 0;
for (b += n, e += n; b < e; b /= 2, e /= 2) {
if (b % 2) res += s[b++];
if (e % 2) res += s[--e];
}
return res;
}
};
ll count_swaps(vi S) {
s = S;
n = sz(s) / 2;
dbg(s);
vector<array<queue<int>, 2>> sizes(n+1);
edge.assign(2*n, -1);
rep(i,0,2*n) {
int size = abs(s[i]);
int right = s[i] > 0;
if(sizes[size][!right].empty())
sizes[size][right].push(i);
else {
int j = sizes[size][!right].front();
sizes[size][!right].pop();
edge[i] = j;
edge[j] = i;
}
}
dbg(edge);
num.assign(2*n, 0);
Tree tree(2*n);
ll res = 0;
rep(i,1,2*n) {
if(edge[i] > i) continue;
res += tree.query(edge[i], i);
tree.update(edge[i], 1);
tree.update(i, 1);
if(s[i] < 0) res++;
}
return res;
}
// 2 3 -4 -2 -3 4 : 3
// 2 -4 -2 4 : +1
// 2 -4 4 -2 : +2
