#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 5, mod = 1e9 + 7;
vector<int> g[maxn], at[8 * maxn];
int vis[maxn];
void update(int id, int l, int r, int p, int val){
at[id].push_back(val);
if(l == r) return;
int mid = (l + r) / 2;
if(p <= mid) update(id * 2, l, mid, p, val);
else update(id * 2 + 1, mid + 1, r, p, val);
}
void query(int id, int l, int r, int u, int v, int val){
if(v < l || r < u) return;
if(u <= l && r <= v){
for(int x: at[id]){
g[val].push_back(x);
g[x].push_back(val);
}
if(at[id].size()) at[id] = {at[id][0]};
return;
}
int mid = (l + r) / 2;
query(id * 2, l, mid, u, v, val);
query(id * 2 + 1, mid + 1, r, u, v, val);
}
bool dfs(int u){
bool res = true;
for(int v: g[u]){
if(!vis[v]){
vis[v] = vis[u] ^ 3;
res &= dfs(v);
}else if(vis[v] == vis[u]) return false;
}
return res;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
int n; cin >> n;
vector<array<int, 2>> a(n + 1);
for(int i = 1; i <= n; i++) cin >> a[i][0] >> a[i][1];
sort(a.begin() + 1, a.end());
for(int i = 1; i <= n; i++){
query(1, 1, 2 * n, a[i][0], a[i][1], i);
update(1, 1, 2 * n, a[i][1], i);
}
int ans = 1;
for(int i = 1; i <= n; i++){
if(vis[i]) continue;
(ans *= 2) %= mod;
vis[i] = 1;
if(!dfs(i)) ans = 0;
}
cout << ans;
return 0;
}
