#include <bits/stdc++.h>
#define f first
#define s second
using namespace std;
typedef pair<int, int> pii;
const int MAXN = 1e6 + 10, mod = 1e9 + 7;
int n, sz[MAXN], w[MAXN][2];
pii p[MAXN], par[MAXN];
vector<int> del;
set<pii> s;
bool use[MAXN], ans = true;
void input() {
cin >> n;
for (int i = 0; i < n; i++)
cin >> p[i].f >> p[i].s;
sort(p, p + n);
}
pii find(int u) {
if (par[u].f == u)
return par[u];
pii res = find(par[u].f);
par[u] = {res.f, res.s ^ par[u].s};
return res;
}
bool merge(int u, int v) {
pii u1 = find(u);
pii v1 = find(v);
if (u1.f == v1.f) {
if (u1 == v1)
return false;
return true;
}
if (sz[u1.f] > sz[v1.f])
swap(u1, v1);
sz[v1.f] += sz[u1.f];
par[u1.f] = {v1.f, ((u1.s ^ v1.s) ^ 1)};
return true;
}
void findComp() {
for (int i = 0; i < n; i++) {
w[i][0] = w[i][1] = -1;
sz[i] = 1;
par[i] = {i, 0};
}
for (int i = 0; i < n; i++) {
if (!s.empty()) {
auto h = s.lower_bound({p[i].f, -1});
for (; h != s.end(); h++) {
int u = (*h).s;
if (p[u].s > p[i].s)
break;
if (!merge(u, i)) {
ans = false;
return;
}
}
}
s.insert({p[i].s, i});
/*del.clear();
if (!s.empty()) {
auto h = s.lower_bound({p[i].s, -1});
for (; h != s.end(); h++) {
int u = (*h).s;
del.push_back(u);
pii u1 = find(u);
w[u1.f][u1.s] = -1;
if (w[u1.f][!u1.s] != -1)
del.push_back(w[u1.f][!u1.s]);
w[u1.f][!u1.s] = -1;
cerr << u << " , " << i << endl;
if (!merge(u, i)) {
ans = false;
return;
}
}
}
del.push_back(i);
int ma[2] = {-1, -1};
for (auto u : del) {
pii u1 = find(u);
if (ma[u1.s] == -1 || p[u].s > p[ma[u1.s]].s)
ma[u1.s] = u;
s.erase({p[u].s, u});
}
del.clear();
int c = find(i).f;
if (ma[0] != -1) {
w[c][0] = ma[0];
s.insert({p[ma[0]].s, ma[0]});
}
if (ma[1] != -1) {
w[c][1] = ma[1];
s.insert({p[ma[1]].s, ma[1]});
}*/
}
}
int findAns() {
for (int i = 0; i < n; i++)
use[find(i).f] = true;
int res = 1;
for (int i = 0; i < n; i++)
if (use[i])
res = (res * 2) % mod;
return res;
}
int main() {
ios::sync_with_stdio(false); cin.tie(0);
input();
findComp();
if (!ans)
cout << 0 << endl;
else
cout << findAns() << endl;
return 0;
}
