#include <bits/stdc++.h>
using namespace std;
typedef signed long long ll;

#define _P(...) (void)printf(__VA_ARGS__)
#define FOR(x,to) for(x=0;x<(to);x++)
#define FORR(x,arr) for(auto& x:arr)
#define FORR2(x,y,arr) for(auto& [x,y]:arr)
#define ALL(a) (a.begin()),(a.end())
#define ZERO(a) memset(a,0,sizeof(a))
#define MINUS(a) memset(a,0xff,sizeof(a))
template<class T> bool chmax(T &a, const T &b) { if(a<b){a=b;return 1;}return 0;}
template<class T> bool chmin(T &a, const T &b) { if(a>b){a=b;return 1;}return 0;}
//-------------------------------------------------------

int N,L[505050],R[505050];

template<class V, int ME> class BIT {
public:
	V bit[1<<ME];
	V operator()(int e) {if(e<0) return 0;V s=0;e++;while(e) s+=bit[e-1],e-=e&-e; return s;}
	void add(int e,V v) { e++; while(e<=1<<ME) bit[e-1]+=v,e+=e&-e;}
};
BIT<ll,21> btL,btR,range;

int ev[1<<20];

void solve() {
	int i,j,k,l,r,x,y; string s;
	
	cin>>N;
	ll sum=0;
	FOR(i,N) {
		cin>>L[i]>>R[i];
		ev[R[i]]=L[i];
		
		sum+=btL(L[i]);
		sum+=btR(1<<20)-btR(R[i]);
		
		btL.add(L[i],1);
		btR.add(R[i],1);
	}
	FOR(i,1<<20) if(ev[i]) {
		x=ev[i];
		sum+=range(1<<20)-range(x);
		range.add(x,1);
	}
	sum-=1LL*N*(N-1)/2;
	cout<<sum/2<<endl;
	
}


int main(int argc,char** argv){
	string s;int i;
	if(argc==1) ios::sync_with_stdio(false), cin.tie(0);
	FOR(i,argc-1) s+=argv[i+1],s+='\n'; FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin);
	cout.tie(0); solve(); return 0;
}