#include "shoes.h"
#include <bits/stdc++.h>
#include <fstream>
#define FIXED_FLOAT(x) std::fixed <<std::setprecision(20) << (x)
#define all(v) (v).begin(), (v).end()
using namespace std;
#define forn(i,n) for (int i = 0; i < (n); ++i)
using ll = long long;
int mod = (ll)1e9 + 7;
#define PI acos(-1)
typedef pair<int, int> pairs;
typedef complex<ll> G;
const int INF = 1e9 + 1;
const int N = 1e6;
const double eps = 1e-3;
using namespace std;
long long count_swaps(std::vector<int> a) {
int n = a.size();
int ans = 0;
vector<bool> vis(n, false);
for(int i =0;i < n;i += 2) {
assert(i + 1 < n);
if(a[i] < 0 && a[i + 1] == a[i] * -1) {
vis[i] = 1;
vis[i + 1] = 1;
continue;
}
int f = a[i] * -1;
int id = -1;
for(int j = i + 1;j < n;++j) {
if(!vis[j] && a[j] == f) {
id = j;
break;
}
}
int from = i;
assert(id != -1);
if(a[i] < 0) {
if(id > from)from++;
}
if(a[i] > 0) {
if(id < from)from--;
}
if(from > id)swap(id, from);
//cout << from << ' ' << id << '\n';
while(id > from) {
swap(a[id], a[id - 1]);
--id;
++ans;
}
vis[i] = 1;
vis[i + 1] = 1;
}
return ans;
}
