#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;
const int inf = 1e9;
int N, l[MAX], r[MAX], inv_from_l[MAX], inv_from_r[MAX], color[MAX];
struct DSU{
int components;
vi lab;
DSU(int n) : lab(n, -1), components(n) {}
int root(int u){
return lab[u] < 0 ? u : (lab[u] = root(lab[u]));
}
bool join(int u, int v){
u = root(u); v = root(v);
if(u == v) return false;
if(lab[u] > lab[v]) swap(u, v);
lab[u] += lab[v]; lab[v] = u; --components;
return true;
}
};
struct SegmentTreeMax{
vi st;
int n;
SegmentTreeMax(int n) : n(n), st(n << 2, -inf) {}
void update(int id, int val){
id += n;
st[id] = val;
for(; id > 1; id >>= 1) st[id >> 1] = max(st[id], st[id^1]);
}
int query(int l, int r){
int mx = -inf;
l += n; r += n+1;
for(; l < r; l >>= 1, r >>= 1){
if(l&1){
maximize(mx, st[l++]);
}
if(r&1){
maximize(mx, st[--r]);
}
}
return mx;
}
};
struct SegmentTreeMin{
vi st;
int n;
SegmentTreeMin(int n) : n(n), st(n << 2, inf) {}
void update(int id, int val){
id += n;
st[id] = val;
for(; id > 1; id >>= 1) st[id >> 1] = min(st[id], st[id^1]);
}
int query(int l, int r){
int mn = inf;
l += n; r += n+1;
for(; l < r; l >>= 1, r >>= 1){
if(l&1){
minimize(mn, st[l++]);
}
if(r&1){
minimize(mn, st[--r]);
}
}
return mn;
}
};
void dfs(int i, SegmentTreeMin& minL, SegmentTreeMax& maxR, DSU& dsu){
//constructing a arbitrary spanning tree
minL.update(r[i], +inf);
maxR.update(l[i], -inf);
while(true){
int lo = minL.query(l[i]+1, r[i]-1);
if(lo < l[i]){
int j = inv_from_l[lo];
color[j] = 3 - color[i];
dsu.join(i, j);
dfs(j, minL, maxR, dsu);
} else break;
}
while(true){
int hi = maxR.query(l[i]+1, r[i]-1);
if(r[i] < hi){
int j = inv_from_r[hi];
color[j] = 3 - color[i];
dsu.join(i, j);
dfs(j, minL, maxR, dsu);
} else break;
}
}
bool check_color(int c){ //checking whether the graph can be bipartite graph
vpi events;
FOR(i, 0, N){
if(color[i] == c){
events.eb(l[i], +(i+1));
events.eb(r[i], -(i+1));
}
}
sort(all(events));
stack<int> online;
FOR(i, 0, sz(events)){
int id = events[i].ss;
if(id > 0) online.push(id);
else{
if(online.top() != -id) return false;
online.pop();
}
}
return true;
}
int main(){
setIO();
cin >> N;
SegmentTreeMin minL(2 * N);
SegmentTreeMax maxR(2 * N);
FOR(i, 0, N){
cin >> l[i] >> r[i];
--l[i], --r[i];
inv_from_l[l[i]] = i;
inv_from_r[r[i]] = i;
minL.update(r[i], l[i]);
maxR.update(l[i], r[i]);
}
DSU dsu(N);
FOR(i, 0, N){
if(!color[i]){
color[i] = 1;
dfs(i, minL, maxR, dsu);
}
}
if(!check_color(1) || !check_color(2)) {
cout << 0 << '\n';
return 0;
}
int ans = 1;
FOR(i, 0, dsu.components){
ans += ans;
if(ans >= mod) ans -= mod;
}
cout << ans << '\n';
return 0;
}
