#include<bits/stdc++.h>
using namespace std;
typedef long double ld;
typedef long long ll;
#define rep(a, b) for(int a = 0; a < (b); ++a)
#define st first
#define nd second
#define pb push_back
#define all(a) a.begin(), a.end()
const ll MOD=1e9+7;
const int LIM=1e6+7;
vector<int>V[LIM];
ll ans=1;
pair<int,int>T[LIM];
int kol[LIM];
void DFS(int x, int o) {
for(auto i : V[x]) {
if(!kol[i]) {
kol[i]=kol[x]^3;
DFS(i, x);
} else if(kol[i]==kol[x]) ans=0;
}
}
int F[LIM], S[2*LIM], odw[LIM], sum[LIM];
int fnd(int x) {
if(F[x]==x) return x;
return F[x]=fnd(F[x]);
}
void uni(int a, int b) {
if(fnd(a)==fnd(b)) return;
F[fnd(b)]=fnd(a);
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0);
int n;
cin >> n;
rep(i, n) {
cin >> T[i].st >> T[i].nd;
--T[i].st; --T[i].nd;
}
sort(T, T+n);
rep(i, n) rep(j, i) if(T[j].st<T[i].st && T[i].st<T[j].nd && T[j].nd<T[i].nd) {
V[i].pb(j);
V[j].pb(i);
}
rep(i, n) if(!kol[i]) {
kol[i]=1;
DFS(i, i);
}
rep(i, n) F[i]=i;
rep(i, n) {
S[T[i].st]=i+1;
S[T[i].nd]=-i-1;
}
vector<int>P;
rep(i, 2*n) {
int p=abs(S[i])-1;
if(S[i]>0) {
P.pb(p);
continue;
}
odw[p]=1;
++sum[P.back()];
--sum[p];
while(P.size()>0 && odw[P.back()]) {
int x=P.back(); P.pop_back();
if(P.size()>0) {
if(sum[x]) uni(x, P.back());
sum[P.back()]+=sum[x];
}
}
}
rep(i, n) if(fnd(i)==i) ans=(ans*2)%MOD;
cout << ans << '\n';
}
