// Author: Kajetan Ramsza
#include "shoes.h"
#include "bits/stdc++.h"
using namespace std;
#define rep(i,a,b) for(int i=(a);i<(b);++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)x.size()
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef long long ll;
#ifdef DEBUG
auto& operator<<(auto& os, const pair<auto, auto> &p);
auto& operator<<(auto &os, const auto &v)
{ os<<"{"; for(auto it=begin(v);it!=end(v);++it) {
if(it != begin(v)) { os<<", "; } os<<(*it);
} return os<<"}"; }
auto& operator<<(auto &os, const pair<auto, auto> &p)
{ return os<<"("<<p.first<<", "<<p.second<<")"; }
void dbg_out(auto... x) { ((cerr<<' '<<x), ...) << endl; }
#define dbg(x...) cerr<<"("<<#x<<"):", dbg_out(x)
#else
#define dbg(...)
#endif
int n;
vi s;
vi edge;
vi num;
void add(int l, int r, int x) {
rep(i,l,r) num[i] += x;
}
set<pii> q;
void swap_elements(int index) {
q.erase({num[index], index});
q.erase({num[index+1], index+1});
if(edge[index] > index) num[index+1]--;
else num[index]++;
if(edge[index+1] > index+1) num[index+1]++;
else num[index]--;
edge[edge[index]] = index+1;
edge[edge[index+1]] = index;
swap(edge[index], edge[index+1]);
swap(s[index], s[index+1]);
if(abs(index - edge[index]) > 1) q.insert({num[index], index});
if(abs(index+1 - edge[index+1]) > 1) q.insert({num[index+1], index+1});
}
ll count_swaps(vi S) {
s = S;
n = sz(s) / 2;
dbg(s);
vector<array<vi, 2>> sizes(n+1);
edge.assign(2*n, -1);
rep(i,0,2*n) {
int size = abs(s[i]);
int right = s[i] > 0;
if(sizes[size][!right].empty())
sizes[size][right].push_back(i);
else {
int j = sizes[size][!right].back();
sizes[size][!right].pop_back();
edge[i] = j;
edge[j] = i;
}
}
dbg(edge);
num.assign(2*n, 0);
rep(i,0,2*n)
if(edge[i] > i)
add(i+1,edge[i],1);
rep(i,0,2*n)
if(abs(i - edge[i]) > 1)
q.insert({num[i], i});
dbg(num);
dbg(q);
int res = 0;
while(!q.empty()) {
int index = (*q.rbegin()).second;
if(abs(index - edge[index]) == 1) {
q.erase({num[index], index});
continue;
}
dbg(index, edge[index]);
if(edge[index] < index) index--;
swap_elements(index);
dbg(edge);
dbg(num);
dbg(q);
res++;
}
for(int i=0;i<2*n;i+=2)
if(s[i] > 0) {
swap(s[i], s[i+1]);
res++;
}
return res;
}
