#include "shoes.h"
#include <bits/stdc++.h>
using namespace std;
#define sp << " " <<
#define nl << "\n"
struct segtree{
int sz = 1;
vector<int> a;
segtree(int n){
while(sz < n) sz *= 2;
a.assign(2*sz, 0);
}
void update(int l, int r, int x, int lx, int rx){
if(rx<=l or r<=lx) return;
if(l<=lx and rx<=r) return void(++a[x]);
int mx = (lx+rx)/2;
update(l, r, 2*x+1, lx, mx);
update(l, r, 2*x+2, mx, rx);
}
void update(int l, int r){ update(l, r, 0, 0, sz); }
int get(int i, int x, int lx, int rx){
if(rx-lx==1) return a[x];
int mx = (lx+rx)/2;
if(i<mx) return a[x] + get(i, 2*x+1, lx, mx);
else return a[x] + get(i, 2*x+2, mx, rx);
}
int get(int i){ return i+get(i, 0, 0, sz); }
};
long long count_swaps(vector<int> s){
int n = ((int)s.size())/2;
segtree st(2*n);
vector<vector<int>> pos0(n), pos1(n);
for(int i=2*n-1; i>=0; --i){
if(s[i]>0) pos1[s[i]-1].push_back(i);
else pos0[-s[i]-1].push_back(i);
}
long long ans = 0;
for(int i=0; i<2*n; ++i){
int curr = abs(s[i])-1;
if((pos0[curr].empty() or pos0[curr].back()!=i)
and (pos1[curr].empty() or pos1[curr].back()!=i)) continue;
int p = s[i] > 0 ? pos0[curr].back() : pos1[curr].back();
int i_ = st.get(i), p_ = st.get(p);
ans += (long long)(p_-i_-(s[i]<0));
st.update(i, p);
pos0[curr].pop_back();
pos1[curr].pop_back();
}
return ans;
}
