#include <bits/stdc++.h>
using namespace std;
#define FOR(i, l, r) for(int i = (l); i < (r); ++i)
#define ROF(i, r, l) for(int i = (r)-1; i >= (l); --i)
#define all(v) begin(v), end(v)
#define rall(v) rbegin(v), rend(v)
#define sz(v) (int)v.size()
#define pb push_back
#define eb emplace_back
#define compact(v) v.erase(unique(all(v)), end(v))
#define mp make_pair
#define mt make_tuple
#define ff first
#define ss second
#define dbg(x) "[" #x " = " << (x) << "]"
template<typename T>
bool minimize(T& a, const T& b){
if(a > b) return a = b, true;
return false;
}
template<typename T>
bool maximize(T& a, const T& b){
if(a < b) return a = b, true;
return false;
}
using ll = long long;
using db = double;
using ld = long double;
using ull = unsigned long long;
using pi = pair<int, int>;
using pl =pair<ll, ll>;
using vi = vector<int>;
using vl = vector<ll>;
using vb = vector<bool>;
using vc = vector<char>;
using vpi = vector<pi>;
using vpl = vector<pl>;
//mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().cout());
//ll random(ll l, ll r){ return uniform_int_distribution<ll>(l, r)(rng); }
void setIO(){
ios_base::sync_with_stdio(0); cin.tie(0);
if(fopen("B.inp", "r")){
freopen("B.inp", "r", stdin);
freopen("B.out", "w", stdout);
}
}
const int MAX = 1e6 + 5;
const int mod = 1e9 + 7;
struct mint{
int v;
mint(int v = 0) : v(v) {}
mint& operator += (const mint& o){
v += o.v;
if(v >= mod) v -= mod;
return *this;
}
mint& operator -= (const mint& o){
v -= o.v;
if(v < 0) v += mod;
return *this;
}
mint& operator *= (const mint& o){
v = 1LL * v * o.v % mod;
return *this;
}
friend mint operator + (mint a, const mint& b){ return a += b; }
friend mint operator - (mint a, const mint& b){ return a -= b; }
friend mint operator * (mint a, const mint& b){ return a *= b; }
friend bool operator == (const mint& a, const mint& b){ return a.v == b.v; }
friend bool operator != (const mint& a, const mint& b){ return a.v != b.v; }
friend ostream& operator << (ostream& out, const mint& o){ return out << o.v; }
};
int N;
pi segments[MAX];
bool can_put(int i, int j){
return (segments[i].ff < segments[j].ff && segments[i].ss > segments[j].ss) || (segments[i].ss < segments[j].ff);
}
namespace subtask1{
bool check(){
return N <= 20;
}
void solve(){
int cnt = 0;
for(int mask = 0; mask < (1 << N); ++mask){
vi A, B;
FOR(i, 0, N){
if(mask >> i & 1){
A.pb(i+1);
} else B.pb(i+1);
}
bool ok = true;
FOR(i, 1, sz(A)){
FOR(j, 0, i){
ok &= can_put(A[j], A[i]);
}
}
FOR(i, 1, sz(B)){
FOR(j, 0, i){
ok &= can_put(B[j], B[i]);
}
}
if(ok){
++cnt;
cout << bitset<8>(mask) << '\n';
}
}
cout << cnt << '\n';
}
}
namespace subtask12{
bool check(){
return N <= 2000;
}
bool vis[2003];
vi adj[2003];
int color[MAX];
void solve(){
int cnt = 0;
FOR(i, 1, N+1){
FOR(j, i+1, N+1){
if(segments[j].ff < segments[i].ss && segments[i].ss < segments[j].ss) {
adj[i].pb(j);
adj[j].pb(i);
++cnt;
// cout << i << ' ' << j << '\n';
}
}
}
cout << cnt << '\n';
// assert(cnt <= 2 * N);
mint ans = 1;
FOR(i, 1, N+1){
if(vis[i]) continue;
queue<int> q;
q.push(i);
vis[i] = true;
// cout << dbg(i) << '\n';
while(!q.empty()){
int u = q.front(); q.pop();
for(auto v : adj[u]){
if(!vis[v]){
color[v] = color[u] ^ 1;
q.push(v);
vis[v] = true;
} else if(color[u] == color[v]){
cout << 0 << '\n';
return;
}
}
}
ans += ans;
}
cout << ans << '\n';
}
}
int main(){
setIO();
cin >> N;
FOR(i, 1, N+1){
cin >> segments[i].ff >> segments[i].ss;
}
sort(segments+1, segments + N+1);
// if(subtask1::check()) return subtask1::solve(), 0;
if(subtask12::check()) return subtask12::solve(), 0;
// subtask34::solve();
return 0;
}
