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#include <bits/stdc++.h>
using namespace std;
typedef vector<int> VI;
typedef pair <int,int> ii;
typedef long long LL;
#define pb push_back
const int INF = 2147483647;
const int MOD = 1000000007;
const int N = 500005;

// rozwiązuje równanie ax=1(%MOD), gdy MOD pierwsze
int inverse(int a) {
    int n = MOD - 2;
    int r = 1;
    while (n) {
   	 if (n % 2) r = (r * 1LL * a) % MOD;
   	 a = (a * 1LL * a) % MOD;
   	 n >>= 1;
    }
    return r;
}

int n, l[N], r[N], i, j, res, act, vis[N], achiev[N];
VI graf[N];
set<ii> s;
set<ii>::iterator it;

void dfs(int w, int st) {
	vis[w] = st;
	achiev[st]++;
	for (auto& w2 : graf[w]) if (vis[w2] != st) dfs(w2, st);
}

int main() {
scanf("%d", &n);
for (i=0;i<n;i++) scanf("%d %d", &l[i], &r[i]);
for (i=n-1;i>=0;i--) {
	it = s.lower_bound(ii(l[i], 0));
	while (it != s.end() && it->first < r[i]) {
		graf[i].pb(it->second);
		s.erase(it++);
	}
	s.insert(ii(l[i], i));
	s.insert(ii(r[i], i));
}
res = 0;
for (i=0;i<n;i++) vis[i] = -1;
for (i=n-1;i>=0;i--) {
	//if (i % 10000 == 0) printf("%d\n", i);
	if (graf[i].size() == 0) achiev[i] = 1; else if (graf[i].size() == 1) achiev[i] = achiev[graf[i][0]] + 1; else dfs(i, i);
	res = (res + inverse(achiev[i])) % MOD;
}
printf("%d\n", res);
return 0;
}