#include <bits/stdc++.h>
using namespace std;
using ll=long long;
const ll ILL=2167167167167167167;
const int INF=2100000000;
#define rep(i,a,b) for (int i=(int)(a);i<(int)(b);i++)
#define all(p) p.begin(),p.end()
template<class T> using _pq = priority_queue<T, vector<T>, greater<T>>;
template<class T> int LB(vector<T> &v,T a){return lower_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> int UB(vector<T> &v,T a){return upper_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> bool chmin(T &a,T b){if(b<a){a=b;return 1;}else return 0;}
template<class T> bool chmax(T &a,T b){if(a<b){a=b;return 1;}else return 0;}
template<class T> void So(vector<T> &v) {sort(v.begin(),v.end());}
template<class T> void Sore(vector<T> &v) {sort(v.begin(),v.end(),[](T x,T y){return x>y;});}
bool yneos(bool a,bool upp=false){if(a){cout<<(upp?"YES\n":"Yes\n");}else{cout<<(upp?"NO\n":"No\n");}return a;}
template<class T> void vec_out(vector<T> &p,int ty=0){
    if(ty==2){cout<<'{';for(int i=0;i<(int)p.size();i++){if(i){cout<<",";}cout<<'"'<<p[i]<<'"';}cout<<"}\n";}
    else{if(ty==1){cout<<p.size()<<"\n";}for(int i=0;i<(int)(p.size());i++){if(i) cout<<" ";cout<<p[i];}cout<<"\n";}}
template<class T> T vec_min(vector<T> &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmin(ans,x);return ans;}
template<class T> T vec_max(vector<T> &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmax(ans,x);return ans;}
template<class T> T vec_sum(vector<T> &a){T ans=T(0);for(auto &x:a) ans+=x;return ans;}
int pop_count(long long a){int res=0;while(a){res+=(a&1),a>>=1;}return res;}
template<class T> T square(T a){return a * a;}

#include <atcoder/segtree>
int op(int a, int b){
    return a + b;
}
int e(){
    return 0;
}

void solve();
// POP'N ROLL MUSIC / TOMOO
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t = 1;
    // cin >> t;
    rep(i, 0, t) solve();
}

void solve(){
    int N;
    cin >> N;
    vector<int> p(N * 2);
    ll ans = 0;
    vector<int> inv(N);
    rep(i, 0, N * 2) cin >> p[i];
    auto f = [&](auto self, int l, int r) -> void {
        if (l + 1 == r) return;
        int m = (l + r) / 2;
        self(self, l, m);
        self(self, m, r);
        vector<int> order1(r - l), order2(r - l);
        rep(i, l, r) order1[i - l] = i, order2[i - l] = i;
        sort(all(order1), [&](int l, int r){
            return p[l * 2] < p[r * 2];
        });
        rep(i, 0, order1.size()) inv[order1[i]] = i;
        sort(all(order2), [&](int l, int r){
            return p[l * 2 + 1] < p[r * 2 + 1];
        });
        atcoder::segtree<int, op, e> seg(r - l);
        // cout << l << " " << m << " " << r << endl;
        for (auto id : order2){
            // cout << id << " " << inv[id] << endl;
            if (id < m){
                ans += seg.prod(inv[id], r - l);
            }
            else{
                seg.set(inv[id], 1);
            }
        }
    };
    f(f, 0, N);
    cout << ans << "\n";
}