#include <bits/stdc++.h>
using namespace std;
#define FOR(i, a, b) for (int i = a; i <= (int)b; i++)
#define FORD(i, a, b) for (int i = a; i >= (int)b; i--)
#define pb push_back
#define fi first
#define se second
#define all(a) a.begin(), a.end()
#define sz(a) (int)a.size()
#define MASK(a) (1LL<<(a))
#define BIT(mask, a) ((mask >> (a))&1)
#define mp make_pair
#define ll long long
#define vI vector <int>
#define pII pair <int, int>
#define vL vector <long long>
template <class A, class B> bool minimize (A &a, const B b) {if (a > b) {a = b;return true;} return false;}
template <class A, class B> bool maximize (A &a, const B b) {if (a < b) {a = b;return true;} return false;}
const int MAXN = 2e5 + 5;
const int MOD = 1e9 + 7;
void add (int &x, const int y) {
x+= y;
if (x >= MOD) x-= MOD;
}
int n;
pII a[MAXN];
void init (void) {
cin >> n;
for (int i = 1; i <= n; i++) {
cin >> a[i].fi >> a[i].se;
}
}
struct DisjointSet {
int lab[MAXN], ssc;
int bipartite = true;
int find (int x) {
return lab[x] < 0 ? x : lab[x] = find(lab[x]);
}
bool joint (int u, int v) {
int x = find(u), y = find(v);
if (x == y) return false;
if (lab[x] > lab[y]) swap (x, y);
lab[x]+= lab[y];
lab[y] = x;
ssc--;
return true;
}
void addNode (int u, int v) {
joint (u, v + n);
joint (v, u + n);
if (find(u) == find(u + n)) {
bipartite = false;
}
if (find(v) == find(v + n)) {
bipartite = false;
}
}
} DSU;
namespace sub2 {
vector <int> G[MAXN];
int vis[MAXN];
void dfs (int u) {
vis[u] = 1;
for (int &v : G[u]) if (!vis[v]) {
dfs(v);
}
}
void solve() {
FOR(i, 1, 2 * n) {
DSU.lab[i] = - 1;
DSU.bipartite = true;
}
DSU.ssc = 2 * n;
sort (a + 1, a + 1 + n, [&] (pII u, pII v) {
return u.second < v.second;
});
FOR(i, 1, n) {
FOR(j, 1, i - 1) {
if ((!(a[i].first > a[j].second)) && (!(a[i].first < a[j].first))) {
DSU.addNode (i, j);
G[i].push_back(j); G[j].push_back(i);
}
}
}
if (!DSU.bipartite) {
cout << 0;
return;
}
int cnt = 0;
FOR(i, 1, n) if (!vis[i]) {
cnt++;
dfs(i);
}
int ans = 1;
FOR(i, 1, cnt) ans = 1LL * ans * 2 % MOD;
cout << ans;
}
}
void process (void) {
if (n <= 2000) {
return sub2::solve();
}
}
signed main (void) {
ios_base::sync_with_stdio(0); cin.tie(0);
#define kieuoanh "concac"
if (fopen(kieuoanh".inp", "r")) {
freopen(kieuoanh".inp", "r", stdin);
freopen(kieuoanh".out", "w", stdout);
}
init();
process();
return 0;
}
