#pragma GCC optimize ("Ofast","unroll-loops")
#include <bits/stdc++.h>
#define pb push_back
#define eb emplace_back
#define MP make_pair
#define F first
#define S second
#define setpre(a) cout.precision(a),cout<<fixed;
#define ALL(a) a.begin(),a.end()
#define MEM(a,b) memset(a,b,sizeof a)
#define Tie ios::sync_with_stdio(0),cin.tie(0);
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<ld,ld> pdd;
struct datas {
int x, y, id;
bool operator<(const datas &a) {
return x < a.x;
}
};
vector<datas> ori, v, tv;
vector<int> C;
int find(int a) {
if(C[a] != a) return C[a] = find(C[a]);
return a;
}
void merge(int a, int b) {
// cout << a << ' ' << b << '\n';
a = find(a);
b = find(b);
if(a == b) return;
C[a] = b;
}
bool is_vali() {
sort(ALL(v));
stack<int> st1, st2;
for(datas &i : v) {
while(!st1.empty() && st1.top() < i.x)
st1.pop();
while(!st2.empty() && st2.top() < i.x)
st2.pop();
if(st1.empty() || st1.top() > i.y)
st1.push(i.y);
else if(st2.empty() || st2.top() > i.y)
st2.push(i.y);
else
return 0;
}
return 1;
}
int main() {Tie
int n;
cin >> n;
v.resize(n), C.resize(n);
for(int i = 0; i < n; i++) {
C[i] = i;
cin >> v[i].x >> v[i].y;
v[i].id = i;
}
ori = v;
if(!is_vali()) {
cout << "0\n";
return 0;
}
v = ori;
sort(ALL(v));
for(int i = 0; i < n; i++) {
for(int j = i + 1; j < n; j++) {
if(v[i].x < v[j].x && v[i].y < v[j].y && v[j].x < v[i].y) {
merge(i, j);
}
}
}
int ans = 1;
for(int i = 0; i < n; i++)
if(C[i] == i)
ans = (ans << 1) % 1000000007;
cout << ans << '\n';
}
