#include <bits/stdc++.h>
#define pb push_back
#define All(x) x.begin(), x.end()
#define pii pair<int,int>
#define ff first
#define ss second
using namespace std;
#define debug(args...) kout("[ " + string(#args) + " ]", args)
void kout() { cerr << endl; }
template <class T, class ...U> void kout(T a, U ...b) { cerr << a << ' ',kout(b...); }
template <class T> void pary(T L, T R) { while (L != R) cerr << *L << " \n"[++L==R]; }
const int MAXN = 1000000;
const int MOD = 1000000007;
int n;
vector <tuple<int,int,int>> qry;
int L[MAXN+1];
int R[MAXN+1];
stack <int> stk;
vector <int> path[MAXN+1];
int vis[MAXN+1];
bool tf = true;
int ans = 1;
void DFS(int now, int flag) {
vis[now] = flag;
for (int i : path[now]) {
if (!vis[i]) {
DFS(i, 3 - flag);
} else {
tf &= (flag + vis[i] == 3);
}
}
}
signed main() {
ios_base::sync_with_stdio(0), cin.tie(0);
cin >> n;
qry.resize(n);
for (int i = 0; i < n; i++) {
auto &[l, r, id] = qry[i];
cin >> l >> r;
id = i+1;
L[id] = l;
R[id] = r;
}
sort(All(qry), [](const tuple<int,int,int> a, const tuple<int,int,int> b) {
return get<1>(a) < get<1>(b);
});
for (int i = 0; i < n; i++) {
auto [l, r, id] = qry[i];
while (stk.size() && l < L[stk.top()])
stk.pop();
if (stk.size() && l < R[stk.top()]) {
path[stk.top()].pb(id);
path[id].pb(stk.top());
}
stk.push(id);
}
while (stk.size()) stk.pop();
sort(All(qry), [](const tuple<int,int,int> a, const tuple<int,int,int> b) {
return get<0>(a) > get<0>(b);
});
for (int i = 0; i < n; i++) {
auto [l, r, id] = qry[i];
while (stk.size() && r > R[stk.top()])
stk.pop();
if (stk.size() && r > L[stk.top()]) {
path[stk.top()].pb(id);
path[id].pb(stk.top());
}
stk.push(id);
}
for (int i = 1; i <= n; i++) {
if (!vis[i]) {
DFS(i, 1);
ans = ans * 2 % MOD;
}
}
sort(All(qry), [](const tuple<int,int,int> a, const tuple<int,int,int> b) {
return get<1>(a) < get<1>(b);
});
while (stk.size()) stk.pop();
for (int i = 0; i < n; i++) {
auto [l, r, id] = qry[i];
if (vis[id] == 2) continue;
while (stk.size() && l < L[stk.top()])
stk.pop();
if (stk.size() && l < R[stk.top()])
tf = false;
stk.push(id);
}
while (stk.size()) stk.pop();
for (int i = 0; i < n; i++) {
auto [l, r, id] = qry[i];
if (vis[id] == 1) continue;
while (stk.size() && l < L[stk.top()])
stk.pop();
if (stk.size() && l < R[stk.top()])
tf = false;
stk.push(id);
}
if (tf)
cout << ans << '\n';
else
cout << 0 << '\n';
return 0;
}
