#include "bits/stdc++.h"
using namespace std;
typedef int ll;
typedef pair<ll, ll> pll;
typedef vector<ll> vll;
const ll N = 1 << 17, mod = 1e9 + 7;
struct node {
vector<pll> v2, og;
set<pll> s;
};
ll n, l[N], r[N], c[N], p[N], id[2 * N], ans = 1, pr[N];
node t[4 * N];
queue<ll> q;
void build(ll v, ll l1, ll r1) {
if (l1 + 1 == r1) {
if (id[l1] != -1) {
t[v].s.insert({r[id[l1]], id[l1]});
t[v].v2 = {{r[id[l1]], id[l1]}};
}
return;
}
ll m = (l1 + r1) / 2;
build(v * 2, l1, m), build(v * 2 + 1, m, r1);
for (auto x: t[v * 2].s) t[v].s.insert(x);
for (auto x: t[v * 2 + 1].s) t[v].s.insert(x);
t[v].v2.resize(t[v * 2].v2.size() + t[v * 2 + 1].v2.size());
merge(t[v * 2].v2.begin(), t[v * 2].v2.end(), t[v * 2 + 1].v2.begin(), t[v * 2 + 1].v2.end(), t[v].v2.begin());
}
void build() {
build(1, 0, 2 * N);
}
ll find_set(ll v) {
return (pr[v] == v ? v : pr[v] = find_set(pr[v]));
}
void union_sets(ll u, ll v) {
u = find_set(u), v = find_set(v);
if (u == v) return;
pr[v] = u;
}
ll getc(ll v, ll l1, ll r1, ll L, ll R) {
if (l1 >= R || r1 <= L) return 0;
if (l1 >= L && r1 <= R) {
if (t[v].v2.size() && c[t[v].v2.back().second]) return 3 - c[t[v].v2.back().second];
return 0;
}
ll m = (l1 + r1) / 2;
return max(getc(v * 2, l1, m, L, R), getc(v * 2 + 1, m, r1, L, R));
}
ll getc(ll l1, ll r1) {
return getc(1, 0, 2 * N, l1, r1);
}
void add3(ll v, ll l1, ll r1, ll L, ll R, ll x, ll i) {
if (l1 >= L || r1 <= 0) return;
if (l1 >= 0 && r1 <= L) {
if (t[v].v2.size() && t[v].v2.back().first > R) union_sets(t[v].v2.back().second, i);
auto it = t[v].s.lower_bound({L, 0});
while (it != t[v].s.end() && it->first < R) {
union_sets((*it).second, i);
if (!c[(*it).second]) c[(*it).second] = x, q.push((*it).second);
t[v].s.erase(it);
it = t[v].s.lower_bound({L, 0});
}
return;
}
ll m = (l1 + r1) / 2;
add3(v * 2, l1, m, L, R, x, i);
add3(v * 2 + 1, m, r1, L, R, x, i);
}
void add3(ll l1, ll r1, ll x, ll i) {
add3(1, 0, 2 * N, l1, r1, x, i);
}
void add1(ll v, ll l1, ll r1, ll L, ll R, ll x, ll i) {
if (l1 >= R || r1 <= L) return;
if (l1 >= L && r1 <= R) {
if (t[v].v2.size() && t[v].v2.back().first > R) union_sets(t[v].v2.back().second, i);
while (t[v].s.size() && (*--t[v].s.end()).first > R) {
union_sets((*--t[v].s.end()).second, i);
if (!c[(*--t[v].s.end()).second]) c[(*--t[v].s.end()).second] = x, q.push((*--t[v].s.end()).second);
t[v].s.erase(--t[v].s.end());
}
return;
}
ll m = (l1 + r1) / 2;
add1(v * 2, l1, m, L, R, x, i);
add1(v * 2 + 1, m, r1, L, R, x, i);
}
void add1(ll l1, ll r1, ll x, ll i) {
add1(1, 0, 2 * N, l1, r1, x, i);
}
void add2(ll v, ll l1, ll r1, ll L, ll R, ll x) {
if (l1 >= R || r1 <= L) return;
if (l1 >= L && r1 <= R) {
t[v].og.push_back({R + 1, x});
return;
}
ll m = (l1 + r1) / 2;
add2(v * 2, l1, m, L, R, x);
add2(v * 2 + 1, m, r1, L, R, x);
}
void add2(ll l1, ll r1, ll x) {
add2(1, 0, 2 * N, l1, r1, x);
}
bool check(ll v, ll l1, ll r1) {
bool f1 = 0, f2 = 0;
ll it = 0;
for (auto [ps, x]: t[v].og) {
while (it < t[v].v2.size() && t[v].v2[it].first < ps) {
if (f1 && c[t[v].v2[it].second] == 2) return 0;
if (f2 && c[t[v].v2[it].second] == 1) return 0;
it++;
}
(x == 1 ? f1 : f2) = 1;
if (it != t[v].v2.size() && f1 && f2) return 0;
}
while (it < t[v].v2.size()) {
if (f1 && c[t[v].v2[it].second] == 2) return 0;
if (f2 && c[t[v].v2[it].second] == 1) return 0;
it++;
}
if (l1 + 1 == r1) return 1;
ll m = (l1 + r1) / 2;
return check(v * 2, l1, m) & check(v * 2 + 1, m, r1);
}
bool check() {
return check(1, 0, 2 * N);
}
signed main() {
ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
cin >> n;
memset(id, -1, sizeof id);
for (ll i = 0; i < n; i++) cin >> l[i] >> r[i], id[l[i]] = i, pr[i] = i;
build();
iota(p, p + n, 0);
sort(p, p + n, [&](ll x, ll y) { return l[x] < l[y]; });
for (ll _ = 0; _ < n; _++) {
if (q.size()) {
ll i = q.front();
q.pop();
add1(l[i], r[i], 3 - c[i], i);
add3(l[i], r[i], 3 - c[i], i);
_--;
} else {
ll i = p[_];
if (c[i]) continue;
ans = (ans * 2) % mod;
if (!c[i]) c[i] = getc(l[i], r[i]);
if (!c[i]) c[i] = 1;
add1(l[i], r[i], 3 - c[i], i);
}
}
sort(p, p + n, [&](ll x, ll y) { return r[x] < r[y]; });
for (ll _ = 0; _ < n; _++) {
ll i = p[_];
add2(l[i], r[i], 3 - c[i]);
}
// for (ll i = 0; i < n; i++) ans = (ans * (1 + (find_set(i) == i))) % mod;
ans *= check();
cout << ans;
}
