#include <bits/stdc++.h>
#ifndef LOCAL
#include "shoes.h"
#endif
using namespace std;
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define Time (clock() * 1.0 / CLOCKS_PER_SEC)
using ll = long long;
using ull = unsigned long long;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
using ld = long double;
template<typename T1, typename T2> bool chkmin(T1& x, T2 y) {
return y < x ? (x = y, true) : false;
}
template<typename T1, typename T2> bool chkmax(T1& x, T2 y) {
return y > x ? (x = y, true) : false;
}
void debug_out() {
cerr << endl;
}
template<typename T1, typename... T2> void debug_out(T1 A, T2... B) {
cerr << ' ' << A;
debug_out(B...);
}
template<typename T> void mdebug_out(T* a, int n) {
for (int i = 0; i < n; ++i)
cerr << a[i] << ' ';
cerr << endl;
}
#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#define mdebug(a, n) cerr << #a << ": ", mdebug_out(a, n)
#else
#define debug(...) 1337
#define mdebug(a, n) 1337
#endif
template<typename T> ostream& operator << (ostream& stream, const vector<T>& v) {
for (auto& x : v)
stream << x << ' ';
return stream;
}
template<typename T1, typename T2> ostream& operator << (ostream& stream, const pair<T1, T2>& p) {
return stream << p.first << ' ' << p.second;
}
const int maxN = 2e5 + 5;
const ll INF64 = 1e18;
int mn[maxN];
ll count_swaps(vector<int> a) {
int n = a.size();
for (auto& x : a) {
if (x < 0) {
x *= -2;
} else {
x = x * 2 + 1;
}
}
ll ans = 0;
for (int i = 0; i < n; i += 2) {
fill(mn, mn + n + 2, -1);
for (int j = 0; j < n; ++j) {
if (a[j] != 0 && mn[a[j]] == -1)
mn[a[j]] = j;
}
ll minF = INF64;
int minX = -1;
for (int x = 1; x <= n / 2; ++x)
if (mn[2 * x] != -1) {
ll f = mn[2 * x] + mn[2 * x + 1];
if (mn[2 * x] > mn[2 * x + 1])
++f;
if (chkmin(minF, f))
minX = x;
}
// ans += minF;
auto f = [&](int j) -> ll {
int res = 0;
while (j > 0) {
res += (a[--j] != 0);
}
return res;
};
int j1 = f(mn[2 * minX]), j2 = f(mn[2 * minX + 1]);
ans += j1 + j2 - 1;
if (j1 > j2) {
swap(j1, j2);
++ans;
}
a[mn[2 * minX]] = a[mn[2 * minX + 1]] = 0;
// rotate(a.begin() + i, a.begin() + j1, a.begin() + j1 + 1);
// rotate(a.begin() + i + 1, a.begin() + j2, a.begin() + j2 + 1);
}
return ans;
}
#ifdef LOCAL
int32_t main() {
#ifdef LOCAL
freopen("in", "r", stdin);
#endif
ios::sync_with_stdio(0);
cin.tie(0);
int n;
assert(1 == scanf("%d", &n));
vector<int> S(2 * n);
for (int i = 0; i < 2 * n; i++)
assert(1 == scanf("%d", &S[i]));
fclose(stdin);
long long result = count_swaps(S);
printf("%lld\n", result);
fclose(stdout);
return 0;
}
#endif
