#include "shoes.h"
#include "bits/stdc++.h"
using namespace std;
long long count_swaps(vector<int> A) {
int64_t N = (int)A.size() >> 1, res = 0;
auto check = [&](const vector<int> &x) -> bool {
for (int i = 1; i < (int)x.size(); i++)
if (!(x[i - 1] < 0 && x[i] > 0 && abs(x[i]) == abs(x[i - 1]))) {
i++;
return false;
}
return true;
};
vector<bool> used(N << 1);
while (!check(A)) {
int L = -1, R = -1, idx = -1;
// for (auto &a : A) cerr << a << ' ';
// cerr << '\n';
for (int i = 0; i < (N << 1); i++) if (!used[i]) {
idx = i;
break;
}
if (idx == -1) break;
if (A[idx] < 0) L = idx;
else R = idx;
for (int i = idx + 1; i < (N << 1); i++) {
if (A[idx] < 0 && A[i] > 0) {
L = idx, R = i;
break;
} else if (A[idx] > 0 && A[i] < 0) {
L = i, R = idx;
break;
}
}
if (L == -1) break;
// cerr << L << ' ' << R << '\n';
int Lel = A[L], Rel = A[R];
if (L < R) res += R - L - 1, A.erase(A.begin() + R), A.insert(A.begin() + L + 1, Rel);
else res += L - R, A.erase(A.begin() + L), A.insert(A.begin() + R, Lel);
used[idx] = used[idx + 1] = true;
}
return res;
}
