#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define f first
#define s second
#define pb push_back
#define ep emplace
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define uniquev(v) sort(all(v)), (v).resize(unique(all(v)) - (v).begin())
#define mem(f,x) memset(f , x , sizeof(f))
#define sz(x) (ll)(x).size()
#define __lcm(a, b) (1ll * ((a) / __gcd((a), (b))) * (b))
#define mxx *max_element
#define mnn *min_element
#define cntbit(x) __builtin_popcountll(x)
#define len(x) (int)(x.length())
const int N = 1e6 + 10;
pair <int, int> parent[N];
int rnk[N], bipartite[N], cnt, id[N * 2];
void make_set(int v) {
parent[v] = make_pair(v, 0);
rnk[v] = 0;
bipartite[v] = true;
}
pair<int, int> find_set(int v) {
if (v != parent[v].first) {
int parity = parent[v].second;
parent[v] = find_set(parent[v].first);
parent[v].second ^= parity;
}
return parent[v];
}
bool add_edge(int a, int b) {
pair<int, int> pa = find_set(a);
a = pa.first;
int x = pa.second;
pair<int, int> pb = find_set(b);
b = pb.first;
int y = pb.second;
if (a == b) {
if (x == y)
bipartite[a] = false;
} else {
cnt--;
if (rnk[a] < rnk[b])
swap (a, b);
parent[b] = make_pair(a, x^y^1);
bipartite[a] &= bipartite[b];
if (rnk[a] == rnk[b])
++rnk[a];
}
return bipartite[a];
}
ll solve() {
vector <pair <int, int>> seg;
int n;
cin >> n;
cnt = n;
for (int i = 1; i <= n; i++) {
int a, b;
cin >> a >> b;
seg.pb({a, b});
}
sort(all(seg));
set <int> save;
for (int i = 0; i < n; i++) {
make_set(i + 1);
id[seg[i].f] = id[seg[i].s] = i + 1;
auto it = save.lower_bound(seg[i].f);
while (it != save.end() && *it < seg[i].s) {
if (add_edge(i + 1, id[*it]) == 0)
return 0;
it = next(it);
}
save.insert(seg[i].s);
}
ll ans = 1, mod = 1e9 + 7;
for (int i = 1; i <= cnt; i++) {
ans = (ans + ans) % mod;
}
return ans;
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t = 1;
//cin >> t;
while (t--) {
cout << solve() << '\n';
}
return 0;
}
