#include "shoes.h"
using namespace std;
class Fenwick
{
vector<int> a;
int count(int right)
{
int cnt = 0;
for (; right >= 0; right = (right & (right + 1)) - 1)
{
cnt += a[right];
}
return cnt;
}
public:
explicit Fenwick(int n)
{
a.assign(n, 0);
}
int count(int left, int right)
{
return count(right) - count(left - 1);
}
void put(int index)
{
for (; index < int(a.size()); index = index | (index + 1))
{
a[index]++;
}
}
};
vector<int> create_index(int n, vector<int> &S)
{
vector<int> index(2 * n + 1);
for (int i = 0; i < 2 * n; i++)
{
index[S[i] + n] = i;
}
return index;
}
long long count_adjacent(int n, vector<int> &S)
{
vector<int> index = create_index(n, S);
Fenwick f = Fenwick(2 * n);
long long ans = 0;
for (int i = 0; i < 2 * n; i++)
{
if (S[i] != 0)
{
int pos = index[-S[i] + n];
ans += pos - i - f.count(i, pos) - (S[i] < 0 ? 1 : 0);
S[pos] = 0;
f.put(pos);
}
}
return ans;
}
vector<int> change(vector<int> v) {
int n = (int)v.size() / 2;
vector<int> cnt(n, 0);
for(int i = 0; i < 2*n; i++)
if(v[i] > 0)
cnt[v[i] - 1]++;
for(int i = 1; i < n; i++)
cnt[i] += cnt[i-1];
vector<int> cntl = cnt, cntr = cnt;
for(int i = 0; i < 2*n; i++)
if(v[i] > 0)
v[i] = (--cntr[v[i] - 1]) + 1;
else
v[i] = -((--cntl[-v[i] - 1]) + 1);
return v;
}
long long count_swaps(vector<int> S)
{
S = change(S);
int n = S.size() / 2;
return count_adjacent(n, S);
}
