#include "shoes.h"
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define fi first
#define se second
#define pb push_back
typedef long long ll;
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef tree<int, null_type, greater<int>, rb_tree_tag, tree_order_statistics_node_update> pbds;
long long count_swaps(std::vector<int> s) {
ll N = s.size() / 2;
int shoes[2 * N];
for (int i = 0; i < 2 * N; i++) {
shoes[i] = s[i];
}
int order[N]; // order of processing shoes
int pm[N + 1] = {0};
int curr = 0;
for (int i = 0; i < 2 * N; i++) {
int val = abs(shoes[i]);
bool toadd = true;
if (pm[val] < 0 && shoes[i] > 0)
toadd = false;
if (pm[val] > 0 && shoes[i] < 0)
toadd = false;
if (toadd) {
order[curr] = val;
curr++;
if (shoes[i] > 0)
pm[val]++;
else
pm[val]--;
}
else {
if (shoes[i] > 0)
pm[val]++;
else
pm[val]--;
}
}
/*
cout<<"order: ";
for (int i = 0; i < N; i++) {
cout<<order[i]<<" ";
}
cout<<endl;
*/
map<ii, int> final;
int counter[N + 1] = {0};
for (int i = 0; i < N; i++) {
final[{-order[i], counter[order[i]]}] = 2 * i;
final[{order[i], counter[order[i]]}] = 2 * i + 1;
counter[order[i]]++;
}
int notsort[2 * N];
int counter2[2 * N + 1] = {0}; // subtract N after
for (int i = 0; i < 2 * N; i++) {
ii val = {shoes[i], counter2[shoes[i] + N]};
counter2[shoes[i] + N]++;
notsort[i] = final[val];
}
/*
cout<<"notsort: ";
for (int i = 0; i < 2 * N; i++) {
cout<<notsort[i]<<" ";
}
cout<<endl;
*/
pbds T;
ll total = 0;
for (int i = 0; i < 2 * N; i++) {
T.insert(notsort[i]);
total += T.order_of_key(notsort[i]);
}
return total;
}
