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

const int base = (1<<20);
int tree[2*base];
void change(int a, int b, int x){
	a += base-1;
	b += base+1;
	while (b-a > 1){
		if (!(a%2)) tree[a+1] = x;
		if (b%2) tree[b-1] = x;
		a /= 2;
		b /= 2;
	}
}
int query(int v){
	v += base;
	int wy = 0;
	while (v){
		wy = max(wy,tree[v]);
		v /= 2;
	}
	return wy;
}	
pair<int,int> kraw[500001];
vector<int> sas[500001];
ll deg[500001];
bitset<50001> dp[50001];
const ll mod = 1e9+7;
ll fastpot(ll a, ll b){
	ll w = 1;
	while (b){
		if (b%2) w = (w*a)%mod;
		a = (a*a)%mod;
		b /= 2;
	}	
	return w%mod;
}
ll inv(ll x){
	return fastpot(x,mod-2);
}
signed main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	ll i;
	int n;
	cin>>n;
	pair<int,int> tab[n+1];
	vector<int> perm;
	for (i = 1; i <= n; i++){
		int a,b;
		cin>>a>>b;
		perm.push_back(i);
		kraw[i] = {query(a),query(b)};
		sas[i].push_back(kraw[i].first);
		sas[i].push_back(kraw[i].second);
		deg[kraw[i].first]++;
		deg[kraw[i].second]++;
		tab[i] = {a,b};
		change(a,b,i);
	}	
	queue<int> Q;
	for (i = 1; i <= n; i++){
		dp[i][i] = 1;
		if (!deg[i]){
			Q.push(i);
		}
	}
	ll wy = 0;
	while (Q.size()){
		int v = Q.front();
		Q.pop();
		wy = (wy+inv(dp[v].count()))%mod;
		for (int u : sas[v]){
			if (!u) continue;
			deg[u]--;
			dp[u] |= dp[v];
			if (!deg[u]) Q.push(u);
		}
	}
	cout<<wy<<"\n";
	return 0;
}