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#include <algorithm>
#include <cstdio>
#include <set>
#include <vector>
using namespace std;

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define VAR(v,w) __typeof(w) v=(w)
#define FORE(it,c) for(VAR(it,(c).begin());it!=(c).end();++it)
#define PB push_back
#define ALL(c) (c).begin(),(c).end()
#define MP make_pair
#define FT first
#define SD second
#define INT(x) int x; scanf("%d", &x)

typedef long long LL;
typedef vector<int> VI;
typedef vector<VI> VVI;

const int mod = 1000000007;
int l[500000], r[500000];
VVI g;
int been[500000];
int c;

int pos(const pair<bool, int>& ee) {
	return ee.FT ? r[ee.SD] : l[ee.SD];
}

bool comp(const pair<bool, int>& e1, const pair<bool, int>& e2) {
	return pos(e1) < pos(e2);
}

void go(int v, int t) {
	if (been[v] == t) return;
	been[v] = t;
	++c;
	FORE(it,g[v]) go(*it, t);
}

inline LL MODL(LL a, LL b) {
	return a >= 0 ? a % b : b + ((a + 1) % b) - 1;
}

LL EXTEUC(LL a, LL b, LL& x, LL& y) {
	x = 1;
	y = 0;
	LL x1 = 0, y1 = 1;
	while (b != 0) {
		LL t = b;
		LL q = a / b;
		b = a % b;
		a = t;
		t = x1;
		x1 = x - q * x1;
		x = t;
		t = y1;
		y1 = y - q * y1;
		y = t;
	}
	return a;
}

LL REVM(LL a, LL m) {
	LL x, y;
	EXTEUC(m, a, x, y);
	return MODL(y, m);
}

int main() {
	INT(n);
	REP(i,n) scanf("%d%d", &l[i], &r[i]);
	vector<pair<bool, int> > e;
	REP(i,n) {
		e.PB(MP(false, i));
		e.PB(MP(true, i));
	}
	sort(ALL(e), comp);
	g.resize(n);
	set<int> s;
	FORE(it,e) {
		if (it->FT) {
			VAR(jt,s.find(-it->SD));
			VAR(kt,jt);
			++kt;
			if (kt != s.end()) g[-*kt].PB(it->SD);
			s.erase(jt);
		} else {
			VAR(jt,s.insert(-it->SD).FT);
			++jt;
			if (jt != s.end()) g[-*jt].PB(it->SD);
		}
	}
	int res = 0;
	REP(i,n) {
		c = 0;
		go(i, i + 1);
		res = (res + REVM(c, mod)) % mod;
	}
	printf("%d\n", res);
}