#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
#define ALL(v) (v).begin(), (v).end()
#define block_of_code if(true)
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll gcd(ll a, ll b){return __gcd(a, b);}
ll lcm(ll a, ll b){return a / gcd(a, b) * b;}
ll LASTBIT(ll mask){return (mask) & (-mask);}
int pop_cnt(ll mask){return __builtin_popcountll(mask);}
int ctz(ull mask){return __builtin_ctzll(mask);}
int logOf(ull mask){return 63 - __builtin_clzll(mask);}
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);}
double rngesus_d(double l, double r){
double cur = rngesus(0, MASK(60) - 1);
cur /= MASK(60) - 1;
return l + cur * (r - l);
}
template <class T1, class T2>
bool maximize(T1 &a, T2 b){
if (a < b) {a = b; return true;}
return false;
}
template <class T1, class T2>
bool minimize(T1 &a, T2 b){
if (a > b) {a = b; return true;}
return false;
}
template <class T>
void printArr(T container, string separator = " ", string finish = "\n", ostream &out = cout){
for(auto item: container) out << item << separator;
out << finish;
}
template <class T>
void remove_dup(vector<T> &a){
sort(ALL(a));
a.resize(unique(ALL(a)) - a.begin());
}
struct DSU{
int n;
vector<pair<int, int>> parent;
vector<int> sz;
bool bipartite = true;
DSU(int _n){
n = _n;
parent.resize(n+1); sz.resize(n+1, 1);
for(int i = 1; i<=n; ++i) parent[i] = {i, 0};
}
pair<int, int> find_set(int u){
if (u == parent[u].first) return make_pair(u, 0);
pair<int, int> v = find_set(parent[u].first);
v.second ^= parent[u].second;
return parent[u] = v;
}
bool same_set(int u, int v){return find_set(u) == find_set(v);}
bool join_set(int u, int v, int w = 1){
pair<int, int> x = find_set(u), y = find_set(v);
u = x.first, v = y.first;
w ^= x.second ^ y.second;
if (u != v){
if (sz[u] < sz[v]) swap(u, v);
parent[v] = {u, w};
sz[u] += sz[v];
return true;
}
if (w == 1) bipartite = false;
return false;
}
int get_size(int u){return sz[find_set(u).first];}
};
int main(void){
ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);
clock_t start = clock();
int n; cin >> n;
vector<pair<int,int>> a(n);
for(int i= 0; i<n; ++i) cin >> a[i].first >> a[i].second;
vector<int> from_left(n*2+1, -1), from_right(n*2+1, -1);
for(int i= 0; i<n; ++i) {
from_left[a[i].first] = from_right[a[i].second] = i;
}
set<int> S;
DSU mst(n);
int cc = n;
for(int i = 1; i<=n*2; ++i){
int j = from_left[i];
if (j == -1) continue;
auto it = S.upper_bound(a[j].first);
while(it != S.end() && (*it) < a[j].second){
int k = from_right[*it];
cc -= mst.join_set(j, k);
it++;
}
S.insert(a[j].second);
}
if (mst.bipartite == false){
cout << 0 << "\n";
exit(0);
}
const int MOD = 1e9 + 7;
int ans = 1;
while(cc--){
ans *= 2;
if (ans >= MOD) ans -= MOD;
}
cout << ans << "\n";
cerr << "Time elapsed: " << clock() - start << " ms\n";
return 0;
}
