#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
const double PI = 4 * atan(1);
#define sz(x) (int)(x).size()
#define ll long long
#define ld long double
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define pii pair <int, int>
#define vi vector<int>
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
#define vpi vector<pair<int, int>>
#define vpd vector<pair<double, double>>
#define pd pair<double, double>
#define f0r(i,a) for(int i=0;i<a;i++)
#define f1r(i,a,b) for(int i=a;i<b;i++)
#define trav(a, x) for (auto& a : x)
template<typename A, typename B> ostream& operator<<(ostream &cout, pair<A, B> const &p) { return cout << "(" << p.f << ", " << p.s << ")"; }
template<typename A> ostream& operator<<(ostream &cout, vector<A> const &v) {
cout << "["; for(int i = 0; i < v.size(); i++) {if (i) cout << ", "; cout << v[i];} return cout << "]";
}
void fast_io(){
ios_base::sync_with_stdio(0);
cin.tie(NULL);
cout.tie(NULL);
}
void io(string taskname){
string fin = taskname + ".in";
string fout = taskname + ".out";
const char* FIN = fin.c_str();
const char* FOUT = fout.c_str();
freopen(FIN, "r", stdin);
freopen(FOUT, "w", stdout);
fast_io();
}
const int MAX = 1e6 + 6;
template<class T, int SZ> struct Seg { // SZ doesn't have to be power of 2
const T ID = 0; // comb(ID,b) must equal b
T comb(T a, T b) { return a+b; } // easily change this to min or max
T seg[2*SZ];
Seg() { memset(seg,0,sizeof seg); }
void pull(int p) { seg[p] = comb(seg[2*p],seg[2*p+1]); }
void reset(){ f0r(i, 2*SZ) seg[i] = 0;}
void upd(int p, T value) { // set value at position p
seg[p += SZ] = value;
for (p /= 2; p; p /= 2) pull(p);
}
T query(int l, int r) { // sum on interval [l, r]
T resl = ID, resr = ID; // make sure non-commutative operations work
for (l += SZ, r += SZ+1; l < r; l /= 2, r /= 2) {
if (l&1) resl = comb(resl,seg[l++]);
if (r&1) resr = comb(seg[--r],resr);
}
return comb(resl,resr);
}
};
const ll MOD = 1e9 + 7;
vpi v;
Seg<int, (1<<21)> seg;
int main(){
fast_io();
int n;
cin >> n;
f0r(i, n){
int ai;
int bi;
cin >> ai >> bi;
v.eb(mp(ai, bi));
}
sort(all(v));
deque<int> a;
deque<int> b;
f0r(i, n){
if(sz(a) == 0){
a.push_back(v[i].s);
continue;
}
else if(sz(b) == 0){
b.push_back(v[i].s);
continue;
}
while(a.front() < v[i].f){
a.pop_front();
}
while(b.front() < v[i].f){
b.pop_front();
}
if(a.front() > v[i].s){
a.push_front(v[i].s);
}
else if(b.front() > v[i].s){
b.push_front(v[i].s);
}
else{
cout << 0 << endl;
return 0;
}
}
int cnt = 0;
for(auto p: v){
int l = p.f;
int r = p.s;
if(seg.query(l, r) == 0){
cnt++;
}
seg.upd(r, 1);
}
ll ans = 1;
f0r(i, cnt){
ans *= 2;
if(ans >= MOD) ans -= MOD;
}
cout << ans << endl;
return 0;
}
