#include "shoes.h"
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
#define mp make_pair
int n;
vector<int> val;
// diff[i] = value(i) - value(i - 1)
vector<int> segtree;
int range_query(int v, int vl, int vr, int ql, int qr) {
if(ql > vr || qr < vl) {
return 0;
}
if(vl == ql && vr == qr) {
return segtree[v];
}
int mid = (vl + vr) / 2;
return range_query(2 * v, vl, mid, ql, min(qr, mid))
+ range_query(2 * v + 1, mid + 1, vr, max(ql, mid + 1), qr);
}
int query(int pos) {
return range_query(1, 1, 2 * n + 1, 1, pos);
}
void point_update(int v, int vl, int vr, int pos, int add) {
if(vl == vr) {
segtree[v] += add;
} else {
int mid = (vl + vr) / 2;
if(pos <= mid) {
point_update(2 * v, vl, mid, pos, add);
} else {
point_update(2 * v + 1, mid + 1, vr, pos, add);
}
segtree[v] = segtree[2 * v] + segtree[2 * v + 1];
}
}
void update(int l, int r, int add) {
point_update(1, 1, 2 * n + 1, l, add);
point_update(1, 1, 2 * n + 1, r + 1, -add);
}
int value_of(int idx) {
return idx + query(idx);
}
int solve() {
int ans = 0;
segtree.assign(1 + 4 * (2 * n + 1), 0);
vector<int> nxt(1 + 2 * n, 0);
vector<int> cur_pos(1 + n, -1);
for(int i = 2 * n; i >= 1; i--) {
if(val[i] > 0) {
nxt[i] = cur_pos[val[i]];
cur_pos[val[i]] = i;
}
}
vector<int> pr(1 + 2 * n, 0);
vector<bool> vis(1 + 2 * n, false);
for(int i = 1; i <= 2 * n; i++) {
if(val[i] < 0) {
int &tmp = cur_pos[-val[i]];
pr[i] = tmp;
pr[tmp] = i;
tmp = nxt[tmp];
}
}
int cnt = 0;
for(int i = 1; i <= 2 * n; i++) {
if(!vis[i]) {
int a = i, b = pr[i];
if(val[a] > 0) {
swap(a, b);
}
vis[a] = true;
vis[b] = true;
cnt++;
ans += value_of(a) - (cnt * 2 - 1);
update(1, a, 1);
ans += value_of(b) - (cnt * 2);
update(1, b, 1);
}
}
return ans;
}
long long count_swaps(vector<signed> s) {
n = s.size() / 2;
val.pb(0);
for(int i = 0; i < 2 * n; i++) {
val.pb(s[i]);
}
return solve();
}
