// include
#include<bits/stdc++.h>
#include "shoes.h"
using namespace std;
// random
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
// templates
template<class X, class Y>
bool maximize(X &x, const Y &y) {
if (y > x) {
x = y;
return (true);
} else return (false);
}
template<class X, class Y>
bool minimize(X &x, const Y &y) {
if (y < x) {
x = y;
return (true);
} else return (false);
}
// define
#define fi first
#define se second
#define pub push_back
#define pob pop_back
#define puf push_front
#define pof pop_front
#define eb emplace_back
#define upb upper_bound
#define lwb lower_bound
#define left VAN
#define right TAN
#define all(a) (a).begin(),(a).end()
#define rall(a) (a).begin(),(a).end()
#define sort_and_unique(a) sort(all(a));(a).resize(unique(all(a))-a.begin())
#define max_ max_element
#define min_ min_element
// another define
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
// limit
const int oo = 2e9;
// function
void yesno(bool x) {
cout << (x ? "YES\n" : "NO\n");
}
#include "shoes.h"
ll count_swaps(vector<int> a) {
int n = (int)a.size() / 2;
ll ans = 0;
for (int i = 0; i < 2 * n; i += 2) {
if (a[i] < 0) {
for (int j = i + 1; j < 2 * n; j++)
if (a[j] == -a[i]) {
ans += j - i - 1;
for (int k = j - 1; k >= i + 1; k--)
swap(a[k], a[k + 1]);
break;
}
} else {
for (int j = i + 1; j < 2 * n; j++)
if (a[j] == -a[i]) {
ans += j - i;
for (int k = j - 1; k >= i; k--)
swap(a[k], a[k + 1]);
break;
}
}
}
return (ans);
}
