#include "shoes.h"
#include <bits/stdc++.h>
using namespace std;
long long count_swaps(std::vector<int> s) {
int n = s.size()/2;
vector<int> v = s;
for (int &i : v) cin >> i;
vector<int> goal;
map<int, int> cnt;
for (int i = 0; i < 2*n; i++) {
int x = v[i];
if (cnt[x] > 0) cnt[x]--;
else {
goal.emplace_back(-abs(x));
goal.emplace_back(abs(x));
cnt[-x]++;
}
}
vector<bool> done(2*n);
vector<int> arr;
for (int i = 0; i < 2*n; i++) {
int j = 0;
for (; j < 2*n; j++) {
if (!done[j] && goal[j] == v[i]) {
break;
}
}
done[j] = 1;
arr.emplace_back(j);
}
int ans = 0;
for (int i = 0; i < 2*n; i++) {
for (int j = 0; j < i; j++) {
if (arr[j] > arr[i]) ans++;
}
}
return ans;
}
