#include "shoes.h"
#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 5;
int n;
long long fen[maxn + 5];
void update(int v, int x) {
for (; v <= 2 * n; v += v & (-v)) {
fen[v] += x;
}
}
long long get(int v) {
long long ans = 0;
for (; v; v -= v & (-v))
ans += fen[v];
return ans;
}
long long count_swaps(vector<int> s) {
n = (int)s.size() / 2;
vector<int> L[n + 1], R[n + 1];
for (int i = 0; i < (int)s.size(); ++i) {
if (s[i] < 0) L[-s[i]].push_back(i + 1);
else R[s[i]].push_back(i + 1);
}
long long res = 0;
vector<pair<int, int>> vec;
for (int i = 1; i <= n; ++i) {
for (int j = 0; j < (int)L[i].size(); ++j) {
int p1 = L[i][j], p2 = R[i][j];
if (p1 > p2) {
res++;
swap(p1, p2);
}
vec.push_back({p1, p2});
}
}
sort(vec.begin(), vec.end());
for (int i = 0; i < (int)vec.size(); ++i) {
long long s1 = get(vec[i].first);
long long s2 = get(vec[i].second);
res += s2 - s1 + 2ll * (i - s2);
update(vec[i].second, 1);
}
return res;
}
