#include "shoes.h"
#include <bits/stdc++.h>
using namespace std;
#define sz(v) (int)(v).size()
typedef long long ll;
const int MAXN = 1e6;
int p[2*MAXN];
vector<int> pos[MAXN+1][2];
struct BIT {
vector<int> bit; int n;
BIT(int _n=0): bit(_n+11, 0), n(_n+10) {}
void update(int i, int v) {
i+=5;
while (i <= n) {
bit[i] += v;
i += (i & -i);
}
}
int sum(int i) {
i+=5;
int res = 0;
while (i > 0) {
res += bit[i];
i -= (i & -i);
}
return res;
}
};
ll count_swaps(vector<int> arr) {
int n = sz(arr) / 2;
// cout << n << endl;
for (int i=0; i<2*n; i++) {
// cout << i << endl;
pos[abs(arr[i])][arr[i] > 0].push_back(i);
p[i] = -1;
}
for (int i=1; i<=2*n; i++)
for (int f=0; f<2; f++) reverse(pos[i][f].begin(), pos[i][f].end());
for (int i=0, pt=0; i<2*n; i++) {
if (p[i] != -1) continue;
// cout << pt << ':' << pos[abs(arr[i])][0].back() << ' ' << pos[abs(arr[i])][1].back() << endl;
p[pos[abs(arr[i])][0].back()] = pt;
p[pos[abs(arr[i])][1].back()] = pt+1;
pos[abs(arr[i])][0].pop_back();
pos[abs(arr[i])][1].pop_back();
pt+=2;
}
// for (int i=0; i<2*n; i++) cout << p[i] << ' ';
// cout << endl;
BIT bit(2*n); ll ans = 0;
for (int i=2*n-1; i>=0; i--) {
ans += bit.sum(p[i]);
bit.update(p[i], 1);
}
return ans;
}
