#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include "dbg.h"
#else
#define dbg(...)
#endif
#define sz(s) (int)(s).size()
#define all(x) (x).begin(), (x).end()
typedef long long ll;
const int inf = 1e9;
const int dx[] = {1, -1, 0, 0};
const int dy[] = {0, 0, 1, -1};
ll count_swaps(vector<int> S)
{
int n = sz(S);
ll ans = 0;
for (int i = 0; i < n; i += 2)
{
//decide which shoes to put here
vector<array<int, 3>> best; // best[i] = {left_index, right_index, swap_count}
int j;
for (j = i+1; j < n; j++)
if (S[j] == -S[i]) break;
assert(j < n);
if (S[i] < 0)
best.push_back({i, j, j - i - 1});
else
best.push_back({j, i+1, j - i});
i++;
if (abs(S[i]) != abs(S[i-1]))
{
for (j = i+1; j < n; j++)
if (S[j] == -S[i]) break;
assert(j < n);
if (S[i] < 0)
best.push_back({i, j, j - i + 1});
else
best.push_back({j, i+1, j - i + 2});
}
i--;
sort(best.rbegin(), best.rend(), [](auto &x, auto &y) { return x[2] < y[2]; });
auto [x, y, z] = best[0];
ans += z;
for (int k = x; k > i; k--)
swap(S[k], S[k-1]);
for (int k = y; k > i+1; k--)
swap(S[k], S[k-1]);
}
return ans;
}
