#include <bits/stdc++.h>
#define long long long
using namespace std;
const long MOD = 1e9+7;
const int N = 1 << 20;
struct seg {
int l, r, i;
seg() { l = r = i = MOD; }
seg(int l, int r, int i): l(l), r(r), i(i) {}
bool operator<(const seg& rhs) const { return l < rhs.l; }
bool operator==(const seg& rhs) const {
if(l == rhs.l) {
assert(i == rhs.i);
return true;
}
return false;
}
};
pair<seg, seg> merge(pair<seg, seg> a, pair<seg, seg> b) {
seg mn1 = seg(), mn2 = seg();
mn1 = min(a.first, b.first);
if(mn1 == a.first) mn2 = min(a.second, min(b.first, b.second));
else mn2 = min(b.second, min(a.first, a.second));
return make_pair(mn1, mn2);
}
int n;
vector<seg> a;
pair<seg, seg> t[N << 1];
void update(int i, seg v) {
i += N;
t[i] = merge({v, seg()}, t[i]);
while(i >>= 1) t[i] = merge(t[i << 1], t[i << 1 | 1]);
}
pair<seg, seg> query(int l, int r) {
pair<seg, seg> ret = {seg(), seg()};
for(l += N, r += N+1; l < r; l >>= 1, r >>= 1) {
if(l & 1) ret = merge(t[l++], ret);
if(r & 1) ret = merge(t[--r], ret);
}
return ret;
}
int dsu[N];
int root(int v) { return (dsu[v] < 0 ? v : dsu[v] = root(dsu[v])); }
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
cin >> n;
for(int i = 0, x, y; i < n; i++) {
cin >> x >> y;
--x, --y;
a.emplace_back(x, y, i);
}
for(int i = 1; i < 2*N; i++) t[i] = {seg(), seg()};
sort(a.begin(), a.end(), [] (auto x, auto y) { return x.r < y.r; });
fill(dsu, dsu+N, -1);
for(seg s: a) {
auto res = query(s.l+1, s.r-1);
// cout << s.l << ' ' << s.r << " pair res" << res.first.l << ' ' << res.second.l << endl;
if(res.second.l < s.l) cout << 0, exit(0);
update(s.r, s);
int u = s.i, v = res.first.i;
if(v != MOD && res.first.l < s.l && (u = root(u)) != (v = root(v))) {
dsu[u] += dsu[v];
dsu[v] = u;
}
}
long ans = 1;
for(int i = 0; i < n; i++) if(root(i) == i) ans = ans * 2 % MOD;
cout << ans;
}
