include<bits/stdc++.h>

using namespace std;
long long n,count_result=0;
int main(){
cin>>n;
vector<pair\<long long,long long>> events(n);
for(long long i=0;i<n;i++)cin>>events[i].first>>events[i].second;
sort(events.begin(),events.end());
multiset<long long> b_values;
for(auto event:events){
long long b=event.second;
auto it=b_values.upper_bound(b);
count_result+=distance(it,b_values.end());
b_values.insert(b);
}
cout<<count_result;
}