#include "bits/stdc++.h"
using namespace std;
#define ar array
typedef long long ll;
const int N = 2e6 + 5;
const int mod = 1e9 + 7;
int a[N], b[N], used[N], c[N];
signed main(){
ios::sync_with_stdio(0); cin.tie(0);
int n; cin >> n;
for(int i=0;i<n;i++){
cin >> a[i] >> b[i];
}
auto is = [&](int i, int j){
if(a[j] < a[i] && a[i] < b[j] && b[j] < b[i]){
return true;
} swap(j, i);
if(a[j] < a[i] && a[i] < b[j] && b[j] < b[i]){
return true;
} return false;
};
vector<int> t[2];
set<ar<int, 2>> inuse;
function<void(int)> dfs = [&](int u){
used[u] = 1;
t[c[u]].push_back(u);
for(int i=0;i<n;i++){
if(used[i]) continue;
if(is(u, i)){
inuse.insert({u, i});
c[i] = c[u] ^ 1;
dfs(i);
}
}
};
int res = 1;
for(int i=0;i<n;i++){
if(used[i]) continue;
inuse.clear();
t[0].clear(), t[1].clear();
dfs(i);
for(auto x : t[0]){
for(auto y : t[1]){
if(is(x, y) && !inuse.count({x, y}) && !inuse.count({y, x})){
cout<<0<<"\n";
return 0;
}
}
}
res = res * 2ll % mod;
}
cout<<res<<"\n";
}
