//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
#include "shoes.h"
using namespace std;
#define ve vector
typedef long long ll;
typedef pair<int, int> pii;
const int INF = 1e9 + 10;
struct SegmentTree {
int Cap;
ve<int> Seg;
int left(int x) { return 2 * x; }
int right(int x) { return 2 * x + 1; }
int parent(int x) { return x / 2; }
void build(int a) {
Cap = 1 << (int)ceil(log2(a));
Seg = ve<int>(2 * Cap);
}
int query(int a, int b) {
return query(a, b, 0, Cap - 1, 1);
}
int query(int a, int b, int i, int j, int curr) {
if (a <= i && j <= b) return Seg[curr];
if (b < i || j < a) return 0;
int m = (i + j) / 2;
return query(a, b, i, m, left(curr)) + query(a, b, m + 1, j, right(curr));
}
void update(int p) {
Seg[Cap + p] = 1;
int curr = parent(Cap + p);
while (curr != 0) {
Seg[curr] = Seg[left(curr)] + Seg[right(curr)];
curr = parent(curr);
}
}
};
ll count_swaps(ve<int> S) {
int n;
ve<int> A;
ve<pii> F;
map<int, pair<ve<int>, ve<int>>> M;
SegmentTree Seg;
n = (int)S.size() / 2;
A = ve<int>(2 * n);
F = ve<pii>(2 * n, {-1, -1});
for (int i = 0; i < 2 * n; i++) {
int s = S[i];
if (s < 0) M[-s].first.push_back(i);
else M[s].second.push_back(i);
}
for (auto x : M) {
int l = (int)x.second.first.size();
for (int i = 0; i < l; i++) {
int a = x.second.first[i];
int b = x.second.second[i];
F[min(a, b)] = {a, b};
}
}
int cnt = 0;
for (int i = 0; i < 2 * n; i++) {
int a, b;
tie(a, b) = F[i];
if (a != -1) {
A[a] = cnt;
A[b] = cnt + 1;
cnt += 2;
}
}
ll ans = 0;
Seg.build(2 * n);
for (int i = 0; i < 2 * n; i++) {
ans += Seg.query(A[i], 2 * n - 1);
Seg.update(A[i]);
}
return ans;
}
