#include <iostream>
#include <fstream>
#include <algorithm>
#include <cstring>
#include <climits>
#include <cassert>
#include <tuple>
#include <queue>
#include <stack>
#include <vector>
#include <map>
#include <set>
#include <string>
#include <unordered_set>
#include <unordered_map>
using namespace std;
typedef long long LL;
typedef vector<int> Vi;
typedef vector<bool> Vb;
typedef vector<vector<int>> Vii;
#define forR(i, n) for (int i = 0; i < (n); i++)
struct SegNode {
SegNode* left = nullptr, * right = nullptr;
int c = 1;
int l, r;
SegNode(int l, int r) {
this->l = l; this->r = r;
if (l != r) {
int mid = (l + r) / 2;
this->left = new SegNode(l, mid);
this->right = new SegNode(mid + 1, r);
c = left->c + right->c;
}
}
int CountRange(int f, int t) {
if (r < f || l > t) return 0;
if (f <= l && r <= t) return c;
return left->CountRange(f, t) + right->CountRange(f, t);
}
void Remove(int x) {
if (r < x || l > x) return;
if (l == x && r == x) {
c = 0;
return;
}
left->Remove(x); right->Remove(x);
c = left->c + right->c;
}
};
vector<queue<int>> poss;
vector<queue<int>> negs;
inline auto& getQueue(int x) {
if (x > 0) return poss[x];
return negs[-x];
}
LL count_swaps(Vi S) {
int n = S.size() / 2;
poss = vector<queue<int>>(n + 3);
negs = vector<queue<int>>(n + 3);
forR(i, 2 * n) {
int c = S[i];
getQueue(c).push(i);
}
LL ans = 0;
if (n <= 1) {
// task 1, 2, 5
forR(i, n) {
int p = i * 2;
int Sp = S[p];
int q = p + 1;
while (S[q] != -Sp) q++;
while (q > p + 1) {
swap(S[q], S[q - 1]);
q--;
ans++;
}
if (S[p] > 0) ans++;
}
} else {
Vb used(2 * n);
SegNode* root = new SegNode(0, 2 * n - 1);
forR(i, 2 * n) {
if (used[i]) continue;
int x = S[i];
int q = getQueue(-x).front();
getQueue(x).pop(); getQueue(-x).pop();
int count = root->CountRange(i, q);
ans += count - 2;
if (x > 0) ans++;
root->Remove(q);
used[q] = true;
}
}
return ans;
}
#ifdef TEST_LOCAL
int main() {
auto c = count_swaps(Vi{ 2, 1, -1, -2 });
c = count_swaps(Vi{ -2, 2, 2, -2, -2, 2 });
return 0;
}
#endif
