#include <bits/stdc++.h>
#include "shoes.h"
using namespace std;
const int maxn = 200200;
struct Fenwick {
int tree[maxn];
void set(int x, int v) {
for (int i = x; i < maxn; i += i & -i) tree[i] += v;
}
int get(int x) {
int res = 0;
for (int i = x; i; i -= i & -i) res += tree[i];
return res;
}
} bit;
long long count_swaps(vector<int> s) {
int n = (int) s.size() / 2;
long long res = 0;
vector<pair<int, int> > v;
vector<pair<int, int> > ord[maxn];
for (int i = 0; i < (int) s.size(); i++) {
ord[abs(s[i])].emplace_back(s[i], i);
}
for (int i = 1; i <= n; i++) {
sort(ord[i].begin(), ord[i].end());
for (int j = 0; j < (int) ord[i].size() / 2; j++) {
int l = ord[i][j].second;
int r = ord[i][j + (int) ord[i].size() / 2].second;
if (l > r) {
swap(l, r); res++;
}
v.emplace_back(l + 1, r + 1);
}
}
for (int i = 1; i <= 2 * n; i++) bit.set(i, 1);
sort(v.begin(), v.end());
for (auto i : v) {
res += bit.get(i.second - 1) - bit.get(i.first);
bit.set(i.first, -1);
bit.set(i.second, -1);
}
return res;
}
