#include "shoes.h"
#include<bits/stdc++.h>
using namespace std;
long long count_swaps(vector<int> s){
long long n = (long long)s.size()/2;
set<pair<long long, long long> > s2;
for(int i = 0; i < 2 * n; i++){
s2.insert(make_pair(i, s[i]));
}
long long ans = 0;
for(int i = 0; i < n; i++){
int cnt = 0;
int idx = -1;
for(auto it : s2){
if(it.second < 0){
ans += cnt;
idx = it.first;
break;
}
cnt++;
}
int cnt2 = -1;
int idx2 = -1;
for(auto it : s2){
if(it.second == -(s2.begin()->second)){
ans += cnt2;
idx2 = it.first;
break;
}
cnt2++;
}
s2.erase(make_pair(idx, s[idx]));
s2.erase(make_pair(idx2, s[idx2]));
}
return ans;
}
