#include <bits/stdc++.h>
using namespace std;
#define int long long
#define form2(i, a, b) for (int i = (a); i < (b); ++i)
#define ford2(i, a, b) for (int i = (a-1); i >= b; --i)
#define form(i, n) form2(i, 0, n)
#define ford(i, n) ford2(i, n, 0)
#define chmax(x, v) x = max(x, (v))
#define chmin(x, v) x = min(x, (v))
#define fi first
#define se second
const long long BIG = 1000000000000000000LL;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
void cpr(string s, vector<int> v)
{ int i = 0; for (char c : s) { if (c == '$') cout << v[i++]; else cout << c; } cout << '\n'; }
void cpr(string s) { cpr(s, {}); }
void solve();
signed main()
{
ios::sync_with_stdio(false);
cin.tie(0);
solve();
return 0;
}
const int borne = 2 * ((int)(1e6) + 5); // MODIF POUR OJ !!!
const int MOD = (int)(1e9) + 7;
int nbCas;
pii cas[borne];
// Union-find
int par[borne];
int sz[borne];
void duInit()
{
form(i, borne) {
par[i] = i;
sz[i] = 1;
}
}
int duFind(int x)
{
if (par[x] == x) return x;
return par[x] = duFind(par[x]);
}
void duUnir(int a, int b)
{
a = duFind(a);
b = duFind(b);
if (a == b) return;
if (sz[a] < sz[b]) swap(a, b); // a devient gros
par[b] = a;
sz[a] += sz[b];
}
// Fin
map<int, int> endToCas;
void solve()
{
duInit();
cin >> nbCas;
form(i, nbCas) cin >> cas[i].fi >> cas[i].se;
sort(cas, cas+nbCas);
form(cur, nbCas) {
int gauche = cas[cur].fi, droite = cas[cur].se;
auto deb = endToCas.lower_bound(gauche);
auto mur = endToCas.lower_bound(droite);
if (mur != endToCas.begin()) {
auto fin = mur; --fin;
while (deb != mur) {
duUnir(cur, deb->se + nbCas);
duUnir(cur + nbCas, deb->se);
if (duFind(deb->se) == duFind(fin->se)) break;
++deb;
}
}
endToCas[droite] = cur;
}
int ans = 1;
form(caisse, nbCas) {
if (duFind(caisse) == caisse) {
ans *= 2;
ans %= MOD;
}
// Non-biparti
if (duFind(caisse) == duFind(caisse + nbCas)) {
cout << "0\n";
return;
}
}
cout << ans << "\n";
}
