#include <bits/stdc++.h>
#include "shoes.h"
using namespace std;
using ll = long long;
using pii = pair<int, int>;
bool check(vector<int> s) {
int n = s.size();
for (int i=0; i<n; i+=2) {
if (s[i]<0 && s[i+1]>0 && abs(s[i]) == s[i+1]) continue;
else return false;
}
return true;
}
long long count_swaps(vector<int> s) {
int n = s.size()/2;
ll ans=0;
while (1) {
if (check(s)) break;
int ordered = 2*n-1;
for (int i=2*n-2; i>=0; i-=2) {
//cout << i << " " << s[i] << " " << s[i+1] << endl;
if (s[i]<0 && s[i+1]>0 && abs(s[i]) == s[i+1]) {
ordered = i-1;
}
else break;
}
//cout << ordered << endl;
if (ordered <= 0) break;
int val = s[ordered];
int idx=ordered-1;
for (int i=ordered-1; i>=0; i--) {
if (abs(s[i]) == abs(val)) {
if ((s[i]>0 && val<0) || (s[i]<0 && val>0)) {
idx = i;
break;
}
}
}
int vall = s[idx];
s.erase(s.begin()+idx);
if (val<0) {
s.insert(s.begin()+ordered, vall);
ans += ordered-idx;
}
else {
s.insert(s.begin()+ordered-1, vall);
ans += (ordered-1)-idx;
}
}
return ans;
}
//3
//-2 2 2 -2 -2 2
